Copper-Catalyzed C–O Bond Formation between Diaryliodonium Salts and Chelating Alcohols

Abstract

We report a copper-catalyzed C–O bond formation using diaryliodonium salts and chelating alcohols. Our protocol operates efficiently under very mild reaction conditions, such as base-free, room temperature, and short reaction time, and uses only 2 mol % Cu₂O without any additional ligands. These features represent a significant advancement over previous methods, which typically require strong bases, high temperature, and/or additional ligands. Various diaryliodonium salts react in high yields with a broad range of diols under our developed conditions. Furthermore, other chelating alcohols, such as β-heteroatom-functionalized alcohols, are also effective at room temperature or slightly higher temperature. This method provides a useful tool for the practical synthesis of aryl alkyl ethers.

Introduction

The formation of C–O bonds is immensely important across diverse fields, including pharmaceuticals, natural products, biomolecules and other functional materials, where C–O bonds are commonly found. − C–O bond formation between aryl halides and aliphatic alcohols largely relies on cost-effective copper-catalyzed reactions. Thus, following the traditional Ullmann-type cross-coupling reactions, which require a stoichiometric amount of copper, strong bases, and high temperature (Figure a), − many other copper-catalyzed C–O bond-forming reactions have been developed. In these reaction, ligands often play an important role: strongly coordinating ligands such as 1,10-phenanthroline, BINAM, and Me₄Ph have been shown to effectively promote reactions with aliphatic alcohols, while several other advanced chelating bidentate ligands have been found to facilitate the reactions under milder conditions. −

1.

C–O bond-forming reaction of aliphatic alcohols. (a) Classical Ullmann-type reaction. (b) C–O bond formation using diaryliodonium salts under metal-free in basic aqueous solution or under copper-catalyzed, basic, high-temperature conditions. (c) This work.

Diaryliodonium salts have emerged as useful substitutes for aryl halides in metal-catalyzed reactions. − Not only are they stable to air and moisture, but they are also more reactive toward nucleophiles than aryl halides due to their strong electron-withdrawing properties and the excellent leaving group ability of their dummy groups. Thus, they are often employed as arylating coupling partners in various O-, N-, and S-arylation reactions. − In particular, the enhanced reactivity of diaryliodonium salts facilitate the oxidative addition and ligand-binding processes under metal catalysis, often enabling milder reaction conditions. , Taking advantage of this high reactivity, C–O bond formation between diaryliodonium salts and aliphatic alcohols has been explored. Olofsson reported that diaryliodonium salts react with relatively reactive aliphatic alcohols such as allylic and benzylic alcohols at 50 °C in the absence of metal; however, the reaction requires an aqueous NaOH solution, which might limit the scope of compatible organic substrates (Figure b). − Meanwhile, Onomura reported that vicinal diols can be arylated using diaryliodonium salts under copper catalytic conditions (10 mol % Cu) in the presence of weak base such as K₃PO₄ (Figure b). , However, these milder conditions ultimately required high reaction temperature and longer reaction times up to 15 h. Still, the combination of reactive diaryliodonium salts and appropriate alcohols such as chelating bidentate diols under copper catalyst appears to be a promising strategy for achieving C–O bond formation under milder conditions. Recently reported synthetic applications of C–O bond formation between diaryliodonium salts and vicinal diols, such as asymmetric desymmetrization of meso 1,2-diols or asymmetric ring-opening of cyclic diaryliodoniums, is worth mentioning. , These asymmetric transformations are nicely carried out with chiral ligands at 40–80 °C for 15–20 h.

In our search for an efficient protocol for C–O bond formation, we previously found that ethylene glycol serves as both an effective bidentate ligand and an O-nucleophile under copper catalysis. , In this system, ethylene glycol cross-coupled with an aryl bromide in the presence of 5 mol % copper catalyst and K₂CO₃ at 130 °C, functioning simultaneously as reagent, ligand, and solvent. Despite the simplicity of this approach, the need for a base and prolonged heating at 130 °C for up to 20 h left room for improvement. Building on these efforts, we sought to incorporate diaryliodonium salts into our developed system. To our delight, we discovered that C–O bond formation between diaryliodonium salts and aliphatic diols, including ethylene glycol, could be achieved under significantly milder conditions (Figure c). The two components cross-coupled under neutral conditions at room temperature within a very short time, using only 2 mol % copper and no additional ligands. In this report, we present our new findings on C–O bond formation leading to aryl alkyl ethers, which stand in contrast to previously reported methods that often require harsh conditions such as strong bases and/or elevated temperature.

Results and Discussion

As an initial trial, di-p-tolyliodonium salt and ethylene glycol were selected for the C–O bond-forming reaction under 10 mol % copper catalysis with KOH as the base. No additional solvent was used, as ethylene glycol was expected to serve as both the reagent and solvent. From the outset, we aimed to perform the reaction at room temperature, anticipating that it might proceed slowly and require an extended reaction time. However, we quickly observed a distinct color change in the reaction mixture, indicating that the reaction was progressing. This prompted us to gradually shorten the reaction time. Remarkably, when Cu₂O was used as the catalyst, the reaction was complete within just 10 min.

With these preliminary results in hand, we further investigated the reaction. Keeping the reaction time fixed at 10 min and the temperature at room temperature, we explored the effect of lowering the copper catalyst loading to 5 mol %. Under these fixed conditions, we examined other variables such as the copper source, the counteranions of the diaryliodonium salt, and the base (Table ). When di-p-tolyliodonium triflate was treated with 1.0 mL of ethylene glycol in the absence of a copper catalyst, no reaction occurred (entry 1, Table ). Although our system could, in principle, adopt the conditions of an aqueous NaOH solution and slight heating, reported by Olofsson, we chose not to pursue this approach in order to develop milder alternative conditions. Accordingly, we first evaluated various copper catalysts, including copper powder and different copper­(I) and copper­(II) salts. Notably, Cu₂O alone proved highly effective in our system, affording the desired product 3ba in 98% GC yield (entry 7, Table ). In contrast, other copper­(I) catalysts, such as copper­(I) halides and copper­(I) acetate, were essentially ineffective even at elevated temperature (90 °C) (entries 3–6, Table ). All copper­(II) catalysts tested were practically inactive at room temperature; in general, they were ineffective regardless of reaction temperature. An exception was Cu­(OAc)₂·H₂O, which showed improved reactivity at 90 °C, affording 3ba in 43% yield (entry 12, Table ). Interestingly, the distinct reactivity of Cu₂O was immediately discernible. Upon mixing di-p-tolyliodonium triflate, ethylene glycol, Cu₂O, and base, the mixture rapidly became homogeneous, accompanied by a slight exothermic response and a color change from reddish to grayish. A comparable phenomenon was observed for Cu­(OAc)₂·H₂O upon heating. In contrast, most other copper salts remained insoluble or poorly dispersed under the conditions.

1. Optimization of Reaction Conditions .

Entry	Cu	X	Base	Yield (%)
1	-	OTf	KOH	0
2	Cu powder	OTf	KOH	0, 0
3	Cul	OTf	KOH	0, 4
4	CuBr	OTf	KOH	0
5	CuCl	OTf	KOH	0
6	CuOAc	OTf	KOH	2, 8
7	Cu2O	OTf	KOH	98
8	CuO	OTf	KOH	0
9	CuCl2	OTf	KOH	6, 10
10	Cu(OH)2	OTf	KOH	0, 6
11	Cu(acac)2	OTf	KOH	3, 4
12	Cu(OAc)2·H2O	OTf	KOH	10, 43
13	CuSO4·5H2O	OTf	KOH	0, 10
14	Cu2O	Br	KOH	0
15	Cu2O	Cl	KOH	0
16	Cu2O	I	KOH	0
17	Cu2O	BF4	KOH	97
18	Cu2O	PF6	KOH	87
19	Cu2O	OTf	NaOH	92
20	Cu2O	OTf	K3PO4	98
21	Cu2O	OTf	Na2CO3	98
22	Cu2O	OTf	NaHCO3	97
23	Cu2O	OTf	---	98
24	Cu2O	OTf	---	96 ,

^aReaction conditions: di-p-tolyliodonium triflate (1b, 1.0 mmol), ethylene glycol (2a, 1.0 mL), copper catalyst (0.05 mmol), and base (3.0 mmol) at room temperature for 10 min.

^bYields determined by GC analysis using dodecane as an internal standard.

^cReaction at 90 °C.

^dCopper catalyst (0.02 mmol).

^eIsolation yield.

Diaryliodonium salts are known to exhibit different reactivities depending on their counteranions under specific reaction conditions. Accordingly, we prepared di-p-tolyliodonium salts bearing various anions and evaluated them to identify the optimal anion for our system. Di-p-tolyliodonium halides such as bromide, chloride, and iodide failed to undergo the reaction (entries 14–16, Table ). In contrast, salts with non-nucleophilic counteranions such as OTf^–, BF₄ ^–, and PF₆ ^– afforded the desired product in excellent yields of 98%, 97%, and 87%, respectively (entries 7, 17, and 18, Table ). This enhanced performance is likely due to their non-nucleophilicity and superior solubility in the reaction medium compared to halide anions. Based on these results, we selected diaryliodonium triflate as the most suitable substrate for our system, as it not only provided high yields but also allowed the synthesis of substrates with various functional groups through the simplest synthetic route.

Contrary to our initial assumption that a strong base was essential for alcohol deprotonation, weaker bases (NaHCO₃, Na₂CO₃, K₃PO₄) afforded comparable yields (97–98%, entries 20–22, Table ), and the reaction proceeded efficiently even without a base (98%, entry 23, Table ). In the absence of base, the reactants dissolved rapidly, accompanied by a color change and mild exotherm. This high intrinsic reactivity allowed reduction of the catalyst loading to 2 mol % Cu₂O without compromising yield (entry 24, Table ).

The combination of the optimal copper catalyst (Cu₂O), a reactive and soluble diaryliodonium triflate, and a chelating bidentate diol proved crucial for achieving C–O coupling under exceptionally mild, room temperature, and base-free conditions. In addition, the nonbasic reaction medium simplified the workup process, allowing product extraction via neutral or slightly acidic aqueous workup.

The optimized reaction conditions (2 mol % Cu₂O, room temperature, 10 min) were then applied to the C–O cross-coupling of ethylene glycol with various diaryliodonium triflates to evaluate the reaction scope (Table ). Diaryliodonium triflates bearing diverse functional groups were prepared according to literature procedures (see Supporting Information). Most were symmetric, while unsymmetric derivatives were synthesized using a mesityl group as the dummy. A broad range of diaryliodonium triflate substrates were readily cross-coupled with ethylene glycol in good to excellent yields, regardless of the electronic nature of the substituents. Both phenyl- and simple alkyl-substituted aryl iodoniums reacted smoothly to afford the corresponding C–O coupled products in excellent yields (3aa–3ea, Table ). Biphenyl iodonium triflate was also effective under the optimized conditions (3fa, Table ). Diaryliodoniums bearing either electron-donating or electron-withdrawing groups were well tolerated. For instance, methoxy- and phenoxy-substituted aryl iodoniums gave the desired products in 62% and 82% yields, respectively (3ga and 3ha, Table ). It is noteworthy that in the case of 3ga, the diaryliodonium tetrafluoroborate salt was used instead of the triflate due to easier synthetic accessibility; the slightly lower yield is likely attributable to the difference in counteranions. Halide-substituted diaryliodoniums, such as 4-chloro, 4-bromo, and 4-fluoro derivatives, also furnished the products in good to excellent yields (3ia, 3la, and 3ma, Table ). Steric effects were evident from the comparison of para-, meta-, and ortho-chloro-substituted aryl iodoniums, with the ortho-chloro derivative giving a lower yield (3ia, 3ja, and 3ka, Table ). Aryl iodoniums containing strong electron-withdrawing groups (e.g., trifluoromethyl) or weaker electron-withdrawing groups (e.g., acetyl) also reacted efficiently (3na and 3oa, Table ). Furthermore, ester functionalities at the para or meta position were tolerated without hydrolysis under our mild, nonaqueous, neutral conditions (3pa and 3qa, Table ). Such ester groups are typically unstable under alkaline aqueous or strongly basic heating conditions. Notably, to the best of our knowledge, C–O bond formation of aliphatic alcohols with aryl iodoniums bearing sensitive functional groups such acetyl and ester has not been reported previously. Overall, our method delivered high yields across a broad scope of diaryliodonium substrates with diverse functional groups.

2. Substrate Scope of C–O Bond Formation: Diaryliodonium Triflates .

^aReaction conditions: diaryliodonium triflate (1, 1.0 mmol), ethylene glycol (2a, 1.0 mL), Cu₂O (0.02 mmol) at room temperature for 10 min; yields refer to isolated products.

^bCounter anion is BF₄ ^–.

Next, we explored the applicability of other aliphatic diols. Unlike ethylene glycol, many aliphatic diols are viscous liquids or solids at room temperature, making them unsuitable for use as solvents. Therefore, we conducted a solvent screening to identify optimal reaction conditions (Table ). When 3.0 equiv of ethylene glycol (2a) were used, good yields of 76% were obtained in either DCM or toluene (entries 1 and 2, Table ). In contrast, polar aprotic solvents such as DMSO and DMF gave poor yields (entries 3 and 4, Table ). Meanwhile, a sufficient amount of ethylene glycol was found to be necessary, as using less than three equivalents of ethylene glycol resulted in poor yields (entries 5 and 6, Table ). It is noteworthy that diarylation of ethylene glycol was not detected under any of the conditions tested, regardless of the amount of ethylene glycol used. Even when diphenyliodonium triflate was applied in a 3-fold excess relative to ethylene glycol, diarylation of ethylene glycol was not observed. For reactions using diols as reactants, DCM was selected as the preferred solvent due to its low boiling point, which facilitates removal during workup, benefiting from the room temperature reactions. Nevertheless, in certain cases, toluene could serve as an alternative to DCM.

3. Solvent Screening for C–O Bond Formation with Diols Used as Reactants .

Entry	2a	Solvent	Yield (%)
1	3.0 equiv	DCM	76
2	3.0 equiv	Touluene	76
3	3.0 equiv	DMF	20
4	3.0 equiv	DMSO	5
5	2.0 equiv	DCM	43
6	1.0 equiv	DCM	40

^aReaction conditions: di-p-tolyliodonium triflate (1a, 1.0 mmol), ethylene glycol (2a, 1–3 equiv), Cu₂O (0.02 mmol) in solvent (1 mL) at room temperature for 10 min.

^bYields determined by GC analysis using dodecane as an internal standard.

With the optimized conditions (3 equiv diol, 2 mol % Cu₂O, DCM), we carried out a substrate scope test using a range of aliphatic diols (Table ). Primary diols with chain lengths of two to five carbons gave decreasing yields with increasing chain length: 2a (76%), 2b (78%), 2c (70%), and 2d (68%), with reaction times extending up to 60 min (entries 1–4, Table ). This trend suggests that shorter diols (C₂–C₃) coordinate more effectively with the copper catalyst and/or diphenyliodonium. Likewise, diol 2e showed an excellent yield, as it has three carbons between the hydroxyl groups. For diol 2f, bearing primary and tertiary hydroxyl groups, C–O coupling occurred selectively at the less hindered primary site. In fact, tertiary diols such as pinacol were ineffective under our conditions, affording less than 10% of the desired C–O coupled product, and heating the reaction mixture to 50 °C resulted in a complex mixture. Although secondary diols possess slightly higher pK _a values and greater steric bulk, which would typically slow the reaction, both acyclic and cyclic secondary diols reacted smoothly with diphenyliodonium triflate within 30 min to afford the corresponding C–O coupled products in 67–80% yields (entries 7–11, Table ). Phenolic 1,2-diol, 2l, and secondary benzylic 1,2-diol, 2m, were also effective under the optimized conditions (entries 12 and 13, Table ). Overall, the protocol is broadly applicable to the arylation of both primary and secondary diols.

4. Substrate Scope of C–O Bond Formation: Aliphatic Diols .

^aReaction conditions: diphenyliodonium triflate (1a, 1.0 mmol), diol (2, 3.0 mmol), Cu₂O (0.02 mmol) in DCM (1 mL) at room temperature.

^bIsolation yield.

To further demonstrate the versatility of the method, alcohols bearing oxygen or nitrogen atoms at the β-position were evaluated, as these can mimic the coordination behavior of 1,2-diols. The β-functionalized alcohols examined included 2-methoxyethanol, 2-phenoxyethanol, 1-hydroxypropan-2-one, 2-pyridinylmethanol, and 2-(phenylamino)­ethanol. These pseudodiol substrates underwent C–O coupling with diaryliodonium triflates under mild, base-free conditions. Reactions of simple substrates, such as diphenyliodonium and alkyl-substituted aryliodoniums with methoxyethanol or phenoxyethanol, proceeded at room temperature (4a, 4b, and 4h, Table ) but were accelerated at 50 °C. Most other combinations required heating at 50 °C for 3 h to reach completion, affording moderate yields, likely due to the reduced bidentate ligand character compared with 1,2-alkane diols. Ester functionalities were well tolerated under these mild, neutral conditions despite the extended heating time (4d, 4i, and 4l, Table ).

5. Substrate Scope of C–O Bond Formation: β-Heteroatom-Functionalized Alcohols .

^aReaction conditions: diaryliodonium triflate (1, 1.0 mmol), alcohol (2, 3.0 mmol), Cu₂O (0.02 mmol) in DCM (1 mL) at room temperature or 50 °C for 3 h; yields refer to isolated products.

^bReaction at 50 °C.

Conclusions

In summary, we have established a copper-catalyzed C–O bond formation strategy that combines the high reactivity of diaryliodonium salts with the chelating ability of diols and β-heteroatom-functionalized alcohols to deliver aryl alkyl ethers under exceptionally mild, base-free conditions. For diols, this ligand-free protocol requires only 2 mol % Cu₂O, proceeds at room temperature in minutes, and accommodates a variety of functional groups, including those sensitive to strong bases or elevated temperature. For β-heteroatom-functionalized alcohols, a slightly elevated temperature was the only additional requirement for efficient conversion. The ability to perform these transformations rapidly and selectively, without compromising functional group compatibility, represents a significant advance over conventional C–O coupling approaches. Beyond providing a practical route to diverse aryl alkyl ethers, the mildness, and operational simplicity of this methodology position it as a valuable platform for complex molecule synthesis and late-stage functionalization in both academic and industrial contexts.

Experimental Section

General Considerations

Copper catalysts with a purity greater than 97% were used. Reagents and solvents were obtained from commercial suppliers and used without further purification. Column chromatography was performed on silica gel 60 (230–400 mesh), and TLC was performed on silica gel 60 F₂₅₄ glass plates. ¹H and ¹³C NMR spectra were recorded on a 500 MHz spectrometer (¹³C at 126 MHz). Multiplicities are denoted as s (singlet), d (doublet), t (triplet), q (quartet), p (pentet), and m (multiplet), with coupling constants (J) reported in hertz (Hz). Chemical shifts are reported in parts per million (ppm) relative to residual solvent peaks or TMS as the internal standard. GC–MS analysis was performed on a GC–MSD system, and GC yields were determined using n-dodecane as an internal calibration standard. High-resolution mass spectrometry (HRMS) was performed for the characterization of new compounds.

Preparation of Diaryliodonium Salts

All diaryliodonium salts were synthesized according to literature procedures and characterized by ¹H and ¹³C NMR spectroscopy (see the Supporting Information).

Synthesis of Aryl Alkyl Ethers via C–O Bond Formation

Procedure A

Diaryliodonium salts (1 mmol), Cu₂O (0.02 mmol), and ethylene glycol (1 mL) were added to a sealed tube under an argon atmosphere. The mixture was stirred at room temperature for the specified time. Upon completion, the reaction mixture was quenched with H₂O and extracted with ethyl acetate. The organic layer was separated, dried over MgSO₄, and concentrated under reduced pressure. The crude product was purified by column chromatography using ethyl acetate/hexanes as the eluent.

Procedure B

Diphenyliodonium triflate (1 mmol), aliphatic diol (3 mmol), Cu₂O (0.02 mmol), and CH₂Cl₂ (1 mL) were added to a sealed tube under an argon atmosphere. The mixture was stirred at room temperature for the specified time. Upon completion, the reaction mixture was acidified with 1 M HCl and extracted with ethyl acetate. The organic layer was separated, dried over MgSO₄, and concentrated under reduced pressure. The crude product was purified by column chromatography using ethyl acetate/hexanes as the eluent.

Procedure C

Diaryliodonium triflate (1 mmol), β-heteroatom-functionalized alcohol (3 mmol), Cu₂O (0.02 mmol), and CH₂Cl₂ (1 mL) were added to a sealed tube under an argon atmosphere. The mixture was stirred at 50 °C for 3 h. Upon completion, the reaction mixture was acidified with 1 M HCl and extracted with ethyl acetate. The organic layer was separated, dried over MgSO₄, and concentrated under reduced pressure. The crude product was purified by column chromatography using ethyl acetate/hexanes as the eluent.

2-Phenoxyethanol (3aa)

Following Procedure A, starting from diphenyliodonium triflate (1.0 mmol), compound 3aa was obtained as a colorless oil (130 mg, 94%). ¹H NMR (500 MHz, CDCl₃) δ 7.31–7.28 (m, 2H), 6.97–6.91 (m, 3H), 4.08 (t, J = 4.0 Hz, 2H), 3.98–3.94 (m, 2H), 2.20 (s, 1H); ¹³C NMR (126 MHz, CDCl₃) δ 158.59, 129.48, 121.01, 114.53, 69.12, 61.22; MS (EI) m/z 138, 94 (100), 77, 66, 51.

2-(p-Tolyloxy)­ethan-1-ol (3ba)

Following Procedure A, starting from di-p-tolyliodonium triflate (1.0 mmol), compound 3ba was obtained as a brown solid (146 mg, 96%). ¹H NMR (500 MHz, CDCl₃) δ 7.08 (d, J = 8.5 Hz, 2H), 6.82 (d, J = 8.5 Hz, 2H), 4.05 (t, J = 5.0 Hz, 2H), 3.96–3.93 (m, 2H), 2.29 (s, 3H), 2.12 (t, J = 5.0 Hz, 1H); ¹³C NMR (126 MHz, CDCl₃) δ 156.59, 130.43, 130.04, 114.53, 69.40, 61.56, 20.54; MS (EI) m/z 152, 108 (100), 91, 77, 65.

2-(m-Tolyloxy)­ethan-1-ol (3ca)

Following Procedure A, starting from di-m-tolyliodonium triflate (1.0 mmol), compound 3ca was obtained as a white solid (145 mg, 95%). ¹H NMR (500 MHz, CDCl₃) δ 7.17 (t, J = 7.8 Hz, 1H), 6.79 (d, J = 7.5 Hz, 1H), 6.76–6.68 (m, 2H), 4.08–4.04 (m, 2H), 3.96–3.92 (m, 2H), 2.33 (s, 3H); ¹³C NMR (126 MHz, CDCl₃) δ 158.74, 139.72, 129.38, 122.09, 115.56, 111.57, 69.19, 61.64, 21.63; MS (EI) m/z 152, 108, 91, 77, 65; FT-IR: 3362, 2923, 2871, 1453, 1376, 997, 855 cm^–1; HRMS (EI) m/z calcd for C₉H₁₂O₂, 152.0837; found, 152.0837.

2-(3,5-Dimethylphenoxy)­ethan-1-ol (3da)

Following Procedure A, starting from bis­(3,5-dimethylphenyl)­iodonium triflate (1.0 mmol), compound 3da was obtained as a colorless oil (141 mg, 85%). ¹H NMR (500 MHz, CDCl₃) δ 6.63 (d, J = 0.5 Hz, 1H), 6.56 (s, 2H), 4.08–4.04 (m, 2H), 3.94 (d, J = 4.2 Hz, 2H), 2.29 (d, J = 1.8 Hz, 6H), 2.04 (t, J = 5.9 Hz, 1H); ¹³C NMR (126 MHz, CDCl₃) δ 158.77, 139.43, 123.04, 112.48, 69.15, 61.69, 21.56; MS (EI) m/z 166, 122 (100), 107, 77.

2-(4-(tert-Butyl)­phenoxy)­ethan-1-ol (3ea)

Following Procedure A, starting from bis­(4-(tert-butyl)­phenyl)­iodonium triflate (1.0 mmol), compound 3ea was obtained as a white solid (183 mg, 94%). ¹H NMR (500 MHz, CDCl₃) δ 7.34–7.28 (m, 2H), 6.90–6.83 (m, 2H), 4.09–4.04 (m, 2H), 3.94 (d, J = 4.0 Hz, 2H), 2.31 (s, 1H), 1.30 (s, 9H); ¹³C NMR (126 MHz, CDCl₃) δ 156.40, 143.79, 126.30, 114.12, 69.31, 61.41, 34.10, 31.56; MS (EI) m/z 194, 179, 135, 107; FT-IR: 3362, 2959, 2868, 1512, 1243, 827 cm^–1; HRMS (EI) m/z calcd for C₁₂H₁₈O₂, 194.1306; found, 194.1306.

2-([1,1’-Biphenyl]-4-yloxy)­ethan-1-ol (3fa)

Following Procedure A, starting from [1,1’-biphenyl]-4-yl­(mesityl)­iodonium triflate (1.0 mmol), compound 3fa was obtained as a white solid (180 mg, 84%). ¹H NMR (500 MHz, CDCl₃) δ 7.54 (t, J = 8.5 Hz, 4H), 7.42 (t, J = 7.6 Hz, 2H), 7.31 (t, J = 7.4 Hz, 1H), 7.00 (d, J = 8.4 Hz, 2H), 4.17–4.11 (m, 2H), 3.99 (dd, J = 9.8, 5.1 Hz, 2H), 2.03 (t, J = 6.3 Hz, 1H); ¹³C NMR (126 MHz, CDCl₃) δ 158.31, 140.84, 134.42, 128.88, 128.38, 126.89, 115.00, 69.42, 61.68; MS (EI) m/z 214, 170, 152, 141, 115.

2-(4-Methoxyphenoxy)­ethan-1-ol (3ga)

Following Procedure A, starting from bis­(4-methoxyphenyl)­iodonium tetrafluoroborate (1.0 mmol), compound 3ga was obtained as a white solid (91 mg, 62%). ¹H NMR (500 MHz, CDCl₃) δ 6.89–6.82 (m, 4H), 4.06–4.02 (m, 2H), 3.97–3.92 (m, 2H), 3.77 (s, 3H), 2.01 (td, J = 6.3, 1.2 Hz, 1H); ¹³C NMR (126 MHz, CDCl₃) δ 154.26, 152.88, 115.73, 114.84, 70.04, 61.74, 55.88; MS (EI) m/z 168, 124 (100), 109, 81.

2-(4-Phenoxyphenoxy)­ethan-1-ol (3ha)

Following Procedure A, starting from mesityl­(4-phenoxyphenyl)­iodonium triflate (1.0 mmol), 3ha was obtained as a white solid (189 mg, 82%). ¹H NMR (500 MHz, CDCl₃) δ 7.34–7.27 (m, 2H), 7.08–7.02 (m, 1H), 7.02–6.87 (m, 6H), 4.09–4.06 (m, 2H), 3.97 (dd, J = 9.7, 5.4 Hz, 2H), 2.01 (t, J = 6.3 Hz, 1H); ¹³C NMR (126 MHz, CDCl₃) δ 158.48, 155.00, 150.73, 129.77, 122.69, 120.93, 117.85, 115.78, 69.85, 61.68; MS (ESI) m/z 230, 186, 157, 109, 77; FT-IR: 3566, 3038, 1376, 1290, 1107, 931, 815 cm^–1; HRMS (EI) m/z calcd for C₁₄H₁₄O₃, 230.0944; found, 230.0942.

2-(4-Chlorophenoxy)­ethan-1-ol (3ia)

Following Procedure A, starting from bis­(4-chlorophenyl)­iodonium triflate (1.0 mmol), compound 3ia was obtained as a colorless liquid (162 mg, 94%). ¹H NMR (500 MHz, CDCl₃) δ 7.26–7.22 (m, 2H), 6.88–6.83 (m, 2H), 4.08–4.03 (m, 2H), 3.96 (dd, J = 9.3, 5.3 Hz, 2H), 2.09–2.03 (m, 1H); ¹³C NMR (126 MHz, CDCl₃) δ 157.31, 129.46, 126.05, 115.91, 69.62, 61.36; MS (EI) m/z 172, 128, 111, 92.

2-(3-Chlorophenoxy)­ethan-1-ol (3ja)

Following Procedure A, starting from bis­(3-chlorophenyl)­iodonium triflate (1.0 mmol), compound 3ja was obtained as a colorless liquid (154 mg, 89%). ¹H NMR (500 MHz, CDCl₃) δ 7.21 (t, J = 8.1 Hz, 1H), 6.96 (ddd, J = 7.9, 1.8, 0.8 Hz, 1H), 6.92 (t, J = 2.2 Hz, 1H), 6.81 (ddd, J = 8.4, 2.5, 0.8 Hz, 1H), 4.07 (dd, J = 5.1, 3.9 Hz, 2H), 3.99–3.94 (m, 2H), 2.06 (s, 1H); ¹³C NMR (126 MHz, CDCl₃) δ 159.44, 135.01, 130.39, 121.40, 115.09, 113.15, 69.57, 61.36; MS (EI) m/z 172, 128, 111, 92.

2-(2-Chlorophenoxy)­ethan-1-ol (3ka)

Following Procedure A, starting from bis­(4-chlorophenyl)­iodonium triflate (1.0 mmol), compound 3ka was obtained as a colorless liquid (121 mg, 70%). ¹H NMR (500 MHz, CDCl₃) δ 7.37 (dt, J = 7.9, 1.4 Hz, 1H), 7.25–7.19 (m, 1H), 6.98–6.90 (m, 2H), 4.17–4.13 (m, 2H), 4.00 (d, J = 4.0 Hz, 2H), 2.25 (s, 1H); ¹³C NMR (126 MHz, CDCl₃) δ 154.25, 130.43, 127.91, 123.26, 122.08, 114.15, 70.79, 61.36; MS (EI) m/z 172, 128, 111, 92; FT-IR: 3364, 2936, 1373, 1162, 794 cm^–1; HRMS (EI) m/z calcd for C₈H₉ClO₂, 172.0288; found, 175.0291.

2-(4-Bromophenoxy)­ethan-1-ol (3la)

Following Procedure A, starting from bis­(4-bromophenyl)­iodonium triflate (1.0 mmol), compound 3la was acquired as a white solid (191 mg, 88%). ¹H NMR (500 MHz, CDCl₃) δ 7.41–7.36 (m, 2H), 6.84–6.78 (m, 2H), 4.08–4.04 (m, 2H), 3.99–3.93 (m, 2H), 2.03–1.94 (m, 1H); ¹³C NMR (126 MHz, CDCl₃) δ 157.78, 132.37, 116.40, 113.31, 69.53, 61.29; MS (EI) m/z 216, 172, 157, 93; FT-IR: 3299, 2922, 2863, 1576, 1364, 1168, 913 cm^–1; HRMS (EI) m/z calcd for C₈H₉BrO₂, 215.9787; found, 215.9785.

2-(4-Fluorophenoxy)­ethan-1-ol (3ma)

Following Procedure A, starting from bis­(4-fluorophenyl)­iodonium triflate (1.0 mmol), compound 3ma was obtained as a white solid (133 mg, 85%). ¹H NMR (500 MHz, CDCl₃) δ 7.02–6.95 (m, 2H), 6.89–6.82 (m, 2H), 4.07–4.03 (m, 2H), 3.95 (d, J = 4.1 Hz, 2H), 2.07 (s, 1H); ¹³C NMR (126 MHz, CDCl₃) δ 158.42, 156.53, 154.81 (d, J = 2.2 Hz), 116.00, 115.89–115.52 (m), 69.98, 61.36; MS (EI) m/z 156, 112, 95, 84.

2-(4-(Trifluoromethyl)­phenoxy)­ethan-1-ol (3na)

Following Procedure A, starting from bis­(4-(trifluoromethyl)­phenyl)­iodonium triflate (1.0 mmol), compound 3na was obtained as a white solid (183 mg, 89%). ¹H NMR (500 MHz, CDCl₃) δ 7.56 (d, J = 8.7 Hz, 2H), 6.99 (d, J = 8.7 Hz, 2H), 4.15–4.11 (m, 2H), 4.00 (dd, J = 9.3, 4.9 Hz, 2H), 2.01 (s, 1H); ¹³C NMR (126 MHz, CDCl₃) δ 161.19, 127.07 (q, J = 3.8 Hz), 125.57, 123.62–123.17 (m), 114.62, 69.54, 61.32; MS (EI) m/z 206, 162, 145, 112, 95; FT-IR: 3299, 2871, 1589, 1424, 950, 733 cm^–1; HRMS (EI) m/z calcd for C₉H₉F₃O₂, 206.0552; found, 206.5004.

1-(4-(2-Hydroxyethoxy)­phenyl)­ethan-1-one (3oa)

Following Procedure A, starting from (4-acetylphenyl)­(mesityl)­iodonium triflate (1.0 mmol), compound 3oa was obtained as a white solid (151 mg, 84%). ¹H NMR (500 MHz, CDCl₃) δ 7.95 (dd, J = 8.9, 1.7 Hz, 2H), 6.96 (dd, J = 8.8, 1.7 Hz, 2H), 4.18–4.13 (m, 2H), 4.01 (dd, J = 9.1, 4.5 Hz, 2H), 2.57 (d, J = 1.7 Hz, 3H), 2.02 (t, J = 5.9 Hz, 1H); ¹³C NMR (126 MHz, CDCl₃) δ 196.95, 162.66, 130.77, 114.34, 69.53, 61.39, 26.49; MS (ESI) m/z 180, 165, 121, 93, 77.

Ethyl 4-(2-Hydroxyethoxy)­benzoate (3pa)

Following Procedure A, starting from (4-(ethoxycarbonyl)-phenyl)-(mesityl)­iodonium triflate (1.0 mmol), compound 3pa was obtained as a colorless oil (177 mg, 78%). ¹H NMR (500 MHz, CDCl₃) δ 8.00 (dd, J = 9.0, 0.7 Hz, 2H), 6.94 (dd, J = 7.6, 1.4 Hz, 2H), 4.40–4.31 (m, 2H), 4.18–4.11 (m, 2H), 4.00 (dd, J = 9.6, 5.1 Hz, 2H), 2.04 (s, 1H), 1.38 (td, J = 7.1, 0.6 Hz, 3H); ¹³C NMR (126 MHz, CDCl₃) δ 166.47, 162.42, 131.70, 123.43, 114.19, 69.46, 61.38, 60.84, 14.48; MS (ESI) m/z 210, 165, 138, 121, 93; FT-IR: 3441, 2936, 1580, 1455 1421 cm^–1; HRMS (EI) m/z calcd for C₁₁H₁₄O₄, 210.0893; found, 210.0892.

Ethyl 3-(2-Hydroxyethoxy)­benzoate (3qa)

Following Procedure A, starting from (3-(ethoxycarbonyl)­phenyl)­(mesityl)­iodonium triflate (1.0 mmol), compound 3qa was obtained as a colorless oil (164 mg, 85%). ¹H NMR (500 MHz, CDCl₃) δ 7.70–7.65 (m, 1H), 7.59 (dd, J = 2.5, 1.4 Hz, 1H), 7.35 (t, J = 8.0 Hz, 1H), 7.12 (ddd, J = 8.2, 2.7, 1.0 Hz, 1H), 4.42–4.34 (m, 2H), 4.17–4.12 (m, 2H), 4.02–3.96 (m, 2H), 2.07 (d, J = 5.2 Hz, 1H), 1.40 (td, J = 7.2, 1.7 Hz, 3H); ¹³C NMR (126 MHz, CDCl₃) δ 166.52, 158.70, 131.99, 129.57, 122.49, 119.86, 114.92, 69.54, 61.48, 61.24, 14.44; MS (ESI) m/z 210, 165, 138, 121, 93; FT-IR: 3415, 2936, 1392, 1171, 807 cm^–1; HRMS (EI) m/z calcd for C₁₁H₁₄O₄, 210.0895; found, 210.0892.

3-Phenoxypropan-1-ol (3ab)

Following Procedure B, starting from propane-1,3-diol (3.0 mmol), compound 3ab was obtained as a colorless liquid (118 mg, 78%). ¹H NMR (500 MHz, CDCl₃) δ 7.32–7.26 (m, 2H), 6.99–6.86 (m, 3H), 4.13 (dd, J = 8.7, 3.3 Hz, 2H), 3.90–3.85 (m, 2H), 2.05 (dq, J = 11.3, 5.6 Hz, 2H), 1.79 (s, 1H); ¹³C NMR (126 MHz, CDCl₃) δ 158.86, 129.60, 121.00, 114.61, 65.80, 60.68, 32.14; MS (EI) m/z 152, 94, 77.

4-Phenoxybutan-1-ol (3ac)

Following Procedure B, starting from butane-1,4-diol (3.0 mmol), compound 3ac was obtained as a colorless liquid (116 mg, 70%). ¹H NMR (500 MHz, CDCl₃) δ 7.32–7.25 (m, 2H), 6.98–6.87 (m, 3H), 4.01 (t, J = 6.2 Hz, 2H), 3.73 (t, J = 6.3 Hz, 2H), 1.89 (dq, J = 8.2, 6.4 Hz, 2H), 1.82–1.72 (m, 2H), 1.60 (s, 1H); ¹³C NMR (126 MHz, CDCl₃) δ 156.7, 148.0, 130.8, 129.3, 126.8, 120.8, 117.9, 113.2, 111.1, 66.5, 43.5, 16.3; MS (EI) m/z 166, 94, 77.

5-Phenoxypentan-1-ol (3ad)

Following Procedure B, starting from propane-1,5-diol (3.0 mmol), compound 3ad was obtained as a colorless liquid (122 mg, 68%). ¹H NMR (500 MHz, CDCl₃) δ 7.31–7.24 (m, 2H), 6.96–6.85 (m, 3H), 3.97 (t, J = 6.4 Hz, 2H), 3.68 (t, J = 6.5 Hz, 2H), 1.87–1.78 (m, 2H), 1.69–1.61 (m, 2H), 1.56 (ddd, J = 12.4, 7.0, 2.2 Hz, 3H); ¹³C NMR (126 MHz, CDCl₃) δ 159.11, 129.51, 120.65, 114.59, 67.78, 62.83, 32.52, 29.16, 22.48; MS (EI) m/z 180, 94, 77.

2,2-Dimethyl-3-phenoxypropan-1-ol (3ae)

Following Procedure B, starting from 2,2-dimethylpropane-1,3-diol (3.0 mmol), compound 3ae was obtained as a colorless liquid (153 mg, 85%). ¹H NMR (500 MHz, CDCl₃) δ 7.32–7.25 (m, 2H), 6.94 (ddd, J = 23.1, 11.7, 4.8 Hz, 3H), 3.78 (s, 2H), 3.56 (s, 2H), 1.92 (s, 1H), 1.04 (s, 6H); ¹³C NMR (126 MHz, CDCl₃) δ 159.13, 129.55, 120.95, 114.64, 74.96, 70.12, 36.49, 21.81; MS (EI) m/z 180, 107, 94, 77.

2-Methyl-4-phenoxybutan-2-ol (3af)

Following Procedure B, starting from 2,2-dimethylpropane-1,3-diol (3.0 mmol), compound 3af was obtained as a colorless liquid (144 mg, 80%). ¹H NMR (500 MHz, CDCl₃) δ 7.29 (dd, J = 8.7, 7.4 Hz, 2H), 6.99–6.94 (m, 1H), 6.94–6.89 (m, 2H), 4.19 (t, J = 6.2 Hz, 2H), 2.33 (s, 1H), 2.00 (t, J = 6.2 Hz, 2H), 1.32 (s, 6H); ¹³C NMR (126 MHz, CDCl₃) δ 158.62, 129.64, 121.15, 114.64, 70.57, 65.22, 41.76, 29.72; MS (EI) m/z 180, 107, 94, 77.

(1R,2S)-1-Phenylpropane-1,2-diol (3ag)

Following Procedure B, starting from (2R,3S)-butane-2,3-diol (3.0 mmol), compound 3ag was obtained as a colorless liquid (133 mg, 80%). ¹H NMR (500 MHz, CDCl₃) δ 7.33–7.24 (m, 2H), 7.00–6.90 (m, 3H), 4.15 (p, J = 6.3 Hz, 1H), 3.95–3.74 (m, 1H), 2.55 (s, 1H), 1.28–1.22 (m, 6H); ¹³C NMR (126 MHz, CDCl₃) δ 157.80, 129.66, 121.34, 116.31, 78.97, 71.01, 18.57, 15.68; MS (EI) m/z 166, 94, 77

(1S,2R)-2-Phenoxycyclopentan-1-ol (3ah)

Following Procedure B, starting from (1R,2S)-cyclopentane-1,2-diol (3.0 mmol), compound 3ah was obtained as a colorless liquid (125 mg, 70%). ¹H NMR (500 MHz, CDCl₃) δ 7.32–7.26 (m, 2H), 7.00–6.91 (m, 3H), 4.54 (dt, J = 6.3, 4.9 Hz, 1H), 4.31–4.22 (m, 1H), 2.42 (t, J = 3.0 Hz, 1H), 2.08–1.98 (m, 1H), 1.98–1.79 (m, 4H), 1.59 (qdd, J = 7.8, 4.2, 2.5 Hz, 1H); ¹³C NMR (126 MHz, CDCl₃) δ 157.68, 129.59, 121.25, 115.80, 79.78, 73.35, 31.22, 28.33, 19.79; MS (EI) m/z 178, 94, 77.

(3S,4R)-4-Phenoxytetrahydrofuran-3-ol (3ai)

Following Procedure B, starting from (3R,4S)-tetrahydrofuran-3,4-diol (3.0 mmol), compound 3ai was obtained as a white solid (126 mg, 70%). ¹H NMR (500 MHz, CDCl₃) δ 7.34–7.28 (m, 2H), 7.03 (tt, J = 7.5, 1.0 Hz, 1H), 6.95–6.90 (m, 2H), 4.76 (dd, J = 10.1, 5.5 Hz, 1H), 4.49 (dq, J = 6.5, 5.4 Hz, 1H), 4.14 (dd, J = 9.9, 5.7 Hz, 1H), 4.04 (dd, J = 9.5, 5.5 Hz, 1H), 3.93 (dd, J = 9.9, 4.5 Hz, 1H), 3.83 (dd, J = 9.5, 5.0 Hz, 1H), 2.61 (d, J = 6.6 Hz, 1H); ¹³C NMR (126 MHz, CDCl₃) δ 157.20, 129.84, 122.12, 115.69, 76.99, 72.96, 71.09, 70.60; MS (EI) m/z 180, 120, 107, 94, 77.

(1S,2R)-2-Phenoxycyclohexan-1-ol (3aj)

Following Procedure B, starting from (1R,2S)-cyclohexane-1,2-diol (3.0 mmol), compound 3aj was obtained as a white solid (129 mg, 67%). ¹H NMR (500 MHz, CDCl₃) δ 7.31–7.25 (m, 2H), 6.96 (ddd, J = 8.7, 7.6, 2.7 Hz, 3H), 4.38 (dt, J = 7.4, 2.8 Hz, 1H), 3.94 (t, J = 6.3 Hz, 1H), 2.20 (d, J = 5.8 Hz, 1H), 2.03–1.86 (m, 2H), 1.76–1.57 (m, 4H), 1.42–1.30 (m, 2H); ¹³C NMR (126 MHz, CDCl₃) δ 157.47, 129.58, 121.29, 116.48, 77.41, 69.33, 30.49, 26.55, 21.77, 21.54; MS (EI) m/z 192, 94, 81, 77.

(1S,2R)-2-Phenoxycyclooctan-1-ol (3ak)

Following Procedure B, starting from (1R,2S)-cyclooctane-1,2-diol (3.0 mmol), compound 3ak was obtained as a white solid (161 mg, 73%). ¹H NMR (500 MHz, CDCl₃) δ 7.32–7.27 (m, 2H), 6.96 (tt, J = 7.6, 1.1 Hz, 1H), 6.92–6.87 (m, 2H), 4.49–4.44 (m, 1H), 4.11–4.05 (m, 1H), 2.54–2.50 (m, 1H), 2.19–2.07 (m, 1H), 2.00–1.89 (m, 1H), 1.86–1.46 (m, 10H); ¹³C NMR (126 MHz, CDCl₃) δ 157.34, 129.61, 121.04, 116.06, 79.67, 71.72, 29.42, 27.01, 26.21, 25.31 (d, J = 18.8 Hz), 21.82; MS (EI) m/z 220, 109, 94, 77.

2-Phenoxyphenol (3al)

Following Procedure B, starting from pyrocatechol (3.0 mmol), compound 3al was obtained as a white solid (121 mg, 65%). ¹H NMR (500 MHz, CDCl₃) δ 7.38–7.31 (m, 2H), 7.12 (ddt, J = 8.5, 7.7, 1.1 Hz, 1H), 7.07–7.00 (m, 4H), 6.86 (dddd, J = 8.7, 8.1, 3.8, 2.2 Hz, 2H), 5.56 (s, 1H); ¹³C NMR (126 MHz, CDCl₃) δ 156.89, 147.63, 143.60, 130.00, 124.90, 123.72, 120.76, 119.02, 118.12, 116.33; MS (EI) m/z 186, 169, 157, 129, 109, 77.

(1R,2R)-2-Phenoxy-1,2-diphenylethan-1-ol (3am)

Following Procedure B, starting from (1R,2S)-1,2-diphenylethane-1,2-diol (3.0 mmol), compound 3am was obtained as a white solid (180 mg, 62%). ¹H NMR (500 MHz, CDCl₃) δ 7.25–7.14 (m, 8H), 7.11 (ddd, J = 5.8, 3.2, 2.1 Hz, 2H), 7.07–7.02 (m, 2H), 6.92–6.84 (m, 3H), 5.10 (d, J = 7.8 Hz, 1H), 4.91 (dd, J = 7.8, 1.9 Hz, 1H), 3.32 (d, J = 1.9 Hz, 1H); ¹³C NMR (126 MHz, CDCl₃) δ 157.74, 138.75, 137.29, 129.53, 128.52, 128.31, 128.23–127.99 (m), 127.56, 127.35, 126.84, 121.52, 116.26, 85.64, 78.78; MS (EI) m/z 290, 183, 167, 155, 105, 94, 77; FT-IR: 3565, 3033, 1596, 1294, 1158, 917, 842 cm^–1; HRMS (EI) m/z calcd for C₂₀H₁₈O₂, 290.1309; found, 290.1306.

2-Methoxyethoxybenzene (4a)

Following Procedure C, starting from diphenyliodonium triflate and 2-methoxyethanol, compound 4a was obtained as a colorless oil (79 mg, 52%). ¹H NMR (500 MHz, CDCl₃) δ 7.30–7.26 (m, 2H), 6.96–6.92 (m, 3H), 4.12 (dd, J = 5.7, 4.0 Hz, 2H), 3.76 (dd, J = 5.4, 4.3 Hz, 2H), 3.46 (s, 3H); ¹³C NMR (126 MHz, CDCl₃) δ 159.0, 129.6, 121.1, 114.8, 71.3, 67.3, 59.5; MS (EI) m/z 152, 107, 94, 77, 59.

1-(2-Methoxyethoxy)-4-methylbenzene (4b)

Following Procedure C, starting from di-p-tolyliodonium triflate and 2-methoxyethanol, compound 4b was obtained as a brown oil (91 mg, 55%). ¹H NMR (500 MHz, CDCl₃) δ 7.07 (d, J = 8.0 Hz, 2H), 6.84–6.82 (m, 2H), 4.10–4.08 (m, 2H), 3.74 (dd, J = 5.4, 4.3 Hz, 2H), 3.45 (s, 3H), 2.28 (s, 3H); ¹³C NMR (126 MHz, CDCl₃) δ 156.7, 130.2, 129.9, 114.6, 71.2, 67.4, 59.3, 20.6; MS (EI) m/z 166, 108, 91, 77, 59; HRMS (EI) m/z calcd for C₁₀H₁₄O₂, 166.0993; found, 166.0993.

1-Phenoxy-2-propanone (4c)

Following Procedure C, starting from diphenyliodonium triflate and 1-hydroxypropan-2-one, compound 4c was obtained as a colorless oil (103 mg, 69%). ¹H NMR (500 MHz, CDCl₃) δ 7.30 (dd, J = 8.8, 7.2 Hz, 2H), 6.99 (t, J = 7.3 Hz, 1H), 6.90–6.85 (m, 2H), 4.53 (s, 2H), 2.28 (s, 3H); ¹³C NMR (126 MHz, CDCl₃) δ 206.1, 157.8, 129.8, 121.8, 114.6, 73.1, 26.7; MS (EI) m/z 150, 107, 77, 51, 43.

Ethyl 3-(2-Oxopropoxy)­benzoate (4d)

Following Procedure C, starting from (3-(ethoxycarbonyl)­phenyl)­(mesityl)­iodonium triflate and 1-hydroxypropan-2-one, compound 4d was obtained as a colorless oil (155 mg, 70%). ¹H NMR (500 MHz, CDCl₃) δ 7.71–7.69 (m, 1H), 7.54 (q, J = 1.3 Hz, 1H), 7.37 (t, J = 8.0 Hz, 1H), 7.11 (dt, J = 7.3, 1.4 Hz, 1H), 4.61 (s, 2H), 4.38 (q, J = 7.1 Hz, 2H), 2.30 (s, 3H), 1.39 (q, J = 6.9 Hz, 3H); ¹³C NMR (126 MHz, CDCl₃) δ 204.9, 166.3, 157.7, 132.1, 129.8, 123.1, 119.7, 114.9, 73.1, 61.3, 26.8, 14.4; MS (EI) m/z 222, 179, 151, 121.

2-(Phenoxymethyl)­pyridine (4e)

Following Procedure C, starting from diphenyliodonium triflate and pyridin-2-ylmethanol, compound 4e was obtained as a colorless oil (109 mg, 59%). ¹H NMR (500 MHz, CDCl₃) δ 8.60 (d, J = 5.7 Hz, 1H), 7.71 (td, J = 7.7, 1.5 Hz, 1H), 7.53 (d, J = 8.0 Hz, 1H), 7.29 (tt, J = 7.0, 2.1 Hz, 2H), 7.22 (dd, J = 7.4, 5.2 Hz, 1H), 7.01–6.95 (m, 3H), 5.22 (s, 2H); ¹³C NMR (126 MHz, CDCl₃) δ 158.3, 157.3, 149.2, 136.8, 129.5, 122.6, 121.3, 121.1, 114.8, 70.5; MS (EI) m/z 185, 168, 130, 92, 65.

2-[(4-Methylphenoxy)­methyl]­pyridine (4f)

Following Procedure C, starting from di-p-tolyliodonium triflate and pyridin-2-ylmethanol, compound 4f was obtained as a brown oil (145 mg, 73%). ¹H NMR (500 MHz, CDCl₃) δ 8.60–8.58 (m, 1H), 7.70 (td, J = 7.7, 1.7 Hz, 1H), 7.52 (d, J = 8.0 Hz, 1H), 7.21 (dd, J = 7.2, 5.4 Hz, 1H), 7.08 (d, J = 8.6 Hz, 2H), 6.88 (dd, J = 6.6, 2.0 Hz, 2H), 5.18 (s, 2H), 2.28 (s, 3H); ¹³C NMR (126 MHz, CDCl₃) δ 157.6, 156.3, 149.2, 136.8, 130.4, 130.0, 122.5, 121.2, 114.6, 70.7, 20.5; MS (EI) m/z 199, 182, 170, 105, 92, 77, 65.

2-[(4-Bromophenoxy)­methyl]­pyridine (4g)

Following Procedure C, starting from bis­(4-bromophenyl)­iodonium triflate and pyridin-2-ylmethanol, compound 4g was obtained as a white solid (106 mg, 40%). ¹H NMR (500 MHz, CDCl₃) δ 8.60 (d, J = 4.6 Hz, 1H), 7.71 (t, J = 7.7 Hz, 1H), 7.48 (d, J = 7.7 Hz, 1H), 7.38 (dd, J = 12.3, 3.7 Hz, 2H), 7.23 (q, J = 4.0 Hz, 1H), 6.88–6.85 (m, 2H), 5.18 (s, 2H); ¹³C NMR (126 MHz, CDCl₃) δ 157.5, 156.8, 149.3, 136.9, 132.4, 122.8, 121.3, 116.6, 113.4, 70.8; MS (EI) m/z 262, 248, 234, 184, 92, 79, 65; HRMS (EI) m/z calcd for C₁₂H₁₀BrNO, 262.9944; found, 262.9945.

1,2-Diphenoxyethane (4h)

Following Procedure C, starting from diphenyliodonium triflate and 2-phenoxyethanol, 4h was obtained as a white solid (182 mg, 85%). ¹H NMR (500 MHz, CDCl₃) δ 7.31–7.28 (m, 4H), 6.98–6.95 (m, 6H), 4.32 (s, 4H); ¹³C NMR (126 MHz, CDCl₃) δ 158.7, 129.6, 121.2, 114.8, 66.5; MS (EI) m/z 214, 121, 91, 77, 65.

Ethyl 3-(2-Phenoxyethoxy)­benzoate (4i)

Following Procedure C, starting from 3-(ethoxycarbonyl)­phenyl)­(mesityl)­iodonium triflate and 2-phenoxyethanol, compound 4i was obtained as a white solid (186 mg, 65%). ¹H NMR (500 MHz, CDCl₃) δ 7.67 (d, J = 7.4 Hz, 1H), 7.63 (t, J = 2.0 Hz, 1H), 7.37–7.29 (m, 3H), 7.17–7.14 (m, 1H), 6.99–6.95 (m, 3H), 4.40–4.33 (m, 6H), 1.39 (dd, J = 8.3, 6.0 Hz, 3H); ¹³C NMR (126 MHz, CDCl₃) δ 166.4, 158.6, 158.6, 131.8, 129.5, 129.4, 122.4, 121.2, 120.0, 114.8, 114.7, 77.3, 77.0, 76.8, 66.7, 66.4, 61.1, 14.3; MS (EI) m/z 286, 241, 192, 147, 121, 91, 77, 65; HRMS (EI) m/z calcd for C₁₇H₁₈O₄, 286.1203; found, 286.1205.

N-(2-Phenoxyethyl)­benzenamine (4j)

Following Procedure C, starting from diphenyliodonium triflate and 2-(phenylamino)­ethanol, compound 4j was obtained as a yellow oil (130 mg, 60%). ¹H NMR (500 MHz, CDCl₃) δ 7.31–7.28 (m, 2H), 7.21–7.18 (m, 2H), 6.98–6.91 (m, 3H), 6.75–6.72 (m, 1H), 6.68 (d, J = 8.0 Hz, 2H), 4.17 (t, J = 5.2 Hz, 2H), 3.53 (t, J = 5.2 Hz, 2H); ¹³C NMR (126 MHz, CDCl₃) δ 158.6, 147.9, 129.5, 129.3, 121.1, 117.9, 114.5, 113.1, 66.4, 43.3; MS (EI) m/z 213, 106, 77.

N-(2-(M -Tolyloxy)­ethyl)­aniline (4k)

Following Procedure C, starting from di-m-tolyliodonium triflate and 2-(phenylamino)­ethanol, compound 4k was obtained as a yellow oil (165 mg, 73%). ¹H NMR (500 MHz, CDCl₃) δ 7.20 (tt, J = 7.6, 1.1 Hz, 2H), 7.17–7.11 (m, 2H), 6.92–6.85 (m, 1H), 6.84–6.80 (m, 1H), 6.74 (td, J = 7.3, 1.2 Hz, 1H), 6.69 (dq, J = 7.5, 1.0 Hz, 2H), 4.17 (t, J = 5.2 Hz, 2H), 4.11 (s, 1H), 3.56 (t, J = 5.2 Hz, 2H), 2.24 (s, 3H); ¹³C NMR (126 MHz, CDCl₃) δ 156.7, 148.0, 130.8, 129.3, 126.8, 120.8, 117.9, 113.2, 111.1, 66.5, 43.5, 16.3; MS (EI) m/z 227, 120, 106, 91, 77, 65; HRMS (EI) m/z calcd for C₁₅H₁₇NO, 227.1313; found, 227.1310.

Ethyl 3-[2-(2-Pyridinyloxy)­ethoxy]­benzoate (4l)

Following Procedure C, starting from 3-(ethoxycarbonyl)­phenyl)­(mesityl)­iodonium triflate and 2-(phenylamino)­ethanol, compound 4l was obtained as a brown solid (286 mg, 83%). ¹H NMR (500 MHz, CDCl₃) δ 7.66 (dd, J = 6.6, 1.4 Hz, 1H), 7.58 (q, J = 1.3 Hz, 1H), 7.35 (t, J = 7.7 Hz, 1H), 7.22–7.18 (m, 2H), 7.11 (dt, J = 9.4, 1.4 Hz, 1H), 6.75 (t, J = 7.2 Hz, 1H), 6.69 (d, J = 8.0 Hz, 2H), 4.38 (q, J = 7.1 Hz, 2H), 4.21 (t, J = 5.2 Hz, 2H), 3.56 (t, J = 5.2 Hz, 2H), 1.39 (td, J = 7.2, 4.6 Hz, 3H); ¹³C NMR (126 MHz, CDCl₃) δ 166.4, 158.6, 147.8, 131.9, 129.4, 129.3, 122.3, 119.7, 118.0, 114.8, 113.2, 66.7, 61.1, 43.2, 14.3; MS (EI) m/z 285, 240, 165, 91, 77; HRMS (EI) m/z calcd for C₁₇H₁₉NO₃, 285.1363; found, 285.1365.

The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/acsomega.5c08197.

• General procedures for the preparation of the starting materials (diaryliodonium salts) and their characterization data, as well as ¹H and ¹³C NMR spectra of the products and the prepared starting materials (PDF)

#.

Energy Storage Research Department, Korea Institute of Energy Research, Daejeon 34129, Republic of Korea

The authors declare no competing financial interest.