3,4,5-Trimeth­oxy-4′-methyl­biphen­yl

Manu Lahtinen; Kalle Nättinen; Sami Nummelin

doi:10.1107/S1600536813010969

. 2013 Apr 30;69(Pt 5):o810–o811. doi: 10.1107/S1600536813010969

3,4,5-Trimethoxy-4′-methylbiphenyl

Manu Lahtinen ^a, Kalle Nättinen ^b, Sami Nummelin ^c,^*

PMCID: PMC3648328 PMID: 23723948

Abstract

In the title compound, C₁₆H₁₈O₃, the dihedral angle between the benzene rings is 33.4 (2)°. In the crystal, molecules are packed in a zigzag arrangement along the b-axis and are interconnected via weak C—H⋯O hydrogen bonds, and C—H⋯π interactions involving the methoxy groups and the benzene rings of neighbouring molecules.

Related literature

For related single-crystal structures based on AB₂– and AB₃-branched biphenyls, see: Lahtinen et al. (2013a ▶,b ▶,c ▶); Lahtinen & Nummelin (2013 ▶). For synthesis of the title compound, see: Percec et al. (2006 ▶, 2007 ▶). For crystal structures of dendrimers, see: Mekelburger et al. (1993 ▶); Nättinen & Rissanen (2003 ▶); Ropponen et al. (2004a ▶). For related Percec-type self-assembling supramolecular dendrimers, see: Percec et al. (2006 ▶, 2007 ▶, 2008 ▶); Roche & Percec (2013 ▶). For dendrimersomes, see: Percec et al. (2010 ▶). For aliphatic and aromatic polyester building blocks for dendrimersomes, see: Ropponen et al. (2004b ▶,c ▶); Nummelin et al. (2000 ▶). graphic file with name e-69-0o810-scheme1.jpg

Experimental

Crystal data

C₁₆H₁₈O₃
M _r = 258.30
Orthorhombic,
a = 8.4669 (2) Å
b = 15.0636 (3) Å
c = 21.4516 (4) Å
V = 2735.98 (10) Å³
Z = 8
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 173 K
0.3 × 0.25 × 0.2 mm

Data collection

Bruker–Nonius KappaCCD diffractometer equipped with an APEXII detector
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ▶) T _min = 0.975, T _max = 0.983
17856 measured reflections
2589 independent reflections
1984 reflections with I > 2σ(I)
R _int = 0.052

Refinement

R[F ² > 2σ(F ²)] = 0.043
wR(F ²) = 0.117
S = 1.03
2589 reflections
173 parameters
H-atom parameters constrained
Δρ_max = 0.28 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Data collection: COLLECT (Nonius, 1998 ▶); cell refinement: SCALEPACK (Otwinowski & Minor, 1997 ▶); data reduction: DENZO (Otwinowski & Minor, 1997 ▶) and SCALEPACK; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: OLEX2 (Dolomanov et al., 2009 ▶) and Mercury (Macrae et al., 2006 ▶); software used to prepare material for publication: OLEX2.

Supplementary Material

Click here for additional data file.^{(24.5KB, cif)}

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536813010969/go2088sup1.cif

e-69-0o810-sup1.cif^{(24.5KB, cif)}

Click here for additional data file.^{(127.3KB, hkl)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536813010969/go2088Isup2.hkl

e-69-0o810-Isup2.hkl^{(127.3KB, hkl)}

Click here for additional data file.^{(5.6KB, cml)}

Supplementary material file. DOI: 10.1107/S1600536813010969/go2088Isup3.cml

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

Cg1 and Cg2 are the centroids of the C2–C7 and C8–C10/C13/C16/C19 aromatic rings, respectively.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C4—H4⋯O11ⁱ	0.95	2.57	3.382 (2)	144
C12—H12B⋯O14ⁱ	0.98	2.56	3.465 (2)	154
C18—H18C⋯O17ⁱⁱ	0.98	2.63	3.488 (2)	146
C15—H15A⋯Cg1ⁱⁱⁱ	0.98	2.84	3.692 (2)	139
C12—H12A⋯Cg2^iv	0.98	3.19	4.061 (2)	132
C18—H18B⋯Cg1^v	0.98	3.01	3.976 (2)	149

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Symmetry codes: (i) Inline graphic ; (ii) ; (iii) ; (iv) ; (v) .

Acknowledgments

SN acknowledges the Academy of Finland for financial support (No. 138850).

supplementary crystallographic information

Comment

3,4,5-Trimethoxy-4'-methyl biphenyl was synthesized in a gram quantities by employing a metal catalyzed coupling reaction between an aryl bromide and p-tolylboronic acid (Percec et al. 2006, 2007). The title compound (I) was used as a building block for the construction of amphiphilic AB₂– and AB₃-branched biphenyl dendrons (Percec et al. 2006) and hybrid (phenyl–biphenyl) dendrons (Percec et al. 2007). With few exceptions (e.g. Mekelburger et al. 1993; Nättinen & Rissanen 2003; Ropponen et al. 2004a) most dendrimers are liquid or amorphous. However, Percec-type dendrons and dendrimers have the ability to self-assemble in the solid state and in selected solvents into supramolecular architectures, such as hollow or non-hollow columns or spheres, which, in turn, self-organize into periodic lattices or quasi-periodic arrays in the solid state (Percec et al. 2006, 2007, 2008). In addition, biphenyls (Percec et al. 2006, 2007) are key building blocks on expanding the scope of libraries of amphiphilic Janus-dendrimers (Ropponen et al. 2004b; Percec et al. 2010) based on hydrophobic Percec-type building blocks and hydrophilic aliphatic and aromatic polyester building blocks. (Ropponen et al. 2004b,c; Nummelin et al. 2000). Amphiphilic Janus-dendrimers self-assemble into uniform liposome-like structures denoted as dendrimersomes (Percec et al. 2010) and other complex adaptable systems (Roche & Percec 2013) in water and selected biological buffers. Herein, we report the title compound 3,4,5-trimethoxy-4'-methyl biphenyl (I) as a contribution to a structural study of biphenyl derivatives (Lahtinen et al. 2013a,b,c; Lahtinen & Nummelin 2013).

Compound (I) has a dihedral angle between the aromatic rings of 33.4 (2)°, and is analogous to various biphenyl structures (Lahtinen et al. 2103a,b). The methoxy groups in 3- and 5-positions (Fig. 1) are co-planar with the [C(8)>C(19)] ring with the dihedral angles of 0.2 (2)° and 0.7 (2)°, respectively, whereas the methoxy group in the 4-position is tilted out from the plane with angle 113.32 (13)°. The molecules are packed in a zigzag formation along b -axis. This formation origates from antiparallel rows of molecules running through c -axis (Figures 2 and 3). Three weak CH···O hydrogen bonds occur with donor-acceptor d(D···A) bond distances of 3.382 (2), 3.465 (2), and 3.488 (2) Å, respectively (Fig. 4). Moreover, a network of weak CH···π interactions is observable between methoxy groups and nearby phenyl groups having ring-centroid to methyl(C) distances of 3.692 (2) - 4.061 (2)Å.

Experimental

A flame-dried Schlenk-tube was loaded with p-tolylboronic acid (3.3 g, 24.3 mmol), KF (2.8 g, 48.6 mmol), 3,4,5-trimethoxy bromobenzene (4.0 g, 16.2 mmol), Pd(OAc)₂ (36 mg, 0.16 mmol, 1.0 mol%) and 2-(di-tert-butylphosphino)biphenyl (97 mg, 0.33 mmol, 2.0 mol%). The tube was sealed with a teflon screwcap and evacuated/backfilled with argon (5x). Then dry, degassed THF (30 ml) was added via syringe and the reaction mixture was stirred at RT until the aryl bromide had been completely consumed as judged by TLC analysis. The mixture was diluted with ether, filtered, and washed with 1M NaOH. The aqueous layer was extracted with ether, the combined organic layer was washed with brine and dried with MgSO₄. After evaporation the pale yellow solid was chromatographed on silica gel using dichloromethane as eluent. Recrystallization from ethanol gave 3.9 g (93%) of the title compound (I) as a white crystalline solid. Crystals suitable for a single-crystal structure determination were obtained from a slow evaporation of the solvent.