Crystal structures and Hirshfeld surface analyses of N,N-di­methyl­acetamide–1-(dimethyl-λ⁴-aza­nyl­idene)ethan-1-ol tribromide (1/1), N,N-di­methyl­acetamide–1-(dimethyl-λ⁴-aza­nyl­idene)ethan-1-ol di­bromido­iodate (1/1) and N,N-di­methyl­acetamide–1-(dimethyl-λ⁴-aza­nyl­idene)ethan-1-ol di­chlorido­iodate (1/1)

In all three title crystals, the cations are linked by O—H⋯O and/or C—H⋯O hydrogen bonds. The three-dimensional packing is further consolidated by strong halogen–hydrogen and weak van der Waals inter­actions.

Abstract

In the title compounds, N,N-di­methyl­acetamide–1-(dimethyl-λ⁴-aza­nyl­idene)ethan-1-ol tribromide (1/1), C₄H₉NO·C₄H₁₀NO⁺·Br₃ ⁻ or [(C₄H₉NO)·(C₄H₁₀NO)](Br₃), (I), N,N-di­methyl­acetamide–1-(dimethyl-λ⁴-aza­nyl­idene)ethan-1-ol di­bromido­iodate (1/1), C₄H₉NO·C₄H₁₀NO⁺·Br₂I⁻ or [(C₄H₉NO)·(C₄H₁₀NO)](Br₂I), (II), and N,N-di­methyl­acetamide–1-(dimethyl-λ⁴-aza­nyl­idene)ethan-1-ol di­chlorido­iodate (1/1), C₄H₉NO·C₄H₁₀NO⁺·Cl₂I⁻ or [(C₄H₉NO)·(C₄H₁₀NO)]·(Cl₂I), (III), all the anions are almost linear in geometry and all the cations, except for the methyl H atoms, are essentially planar. In the crystal structure of (I), the cations are linked by pairs of C—H⋯O hydrogen bonds, forming inversion dimers with an R ₂ ²(8) ring motif. These dimers also exhibit O—H⋯O hydrogen bonding. Dimerized cation pairs and anions are arranged in columns along the a axis. In the crystal of (II), the cations are linked by pairs of O—H⋯O and C—H⋯O hydrogen bonds, forming an R ₄ ⁴(14) ring motif. These groups of cations and the anions form individual columns along the a axis and jointly reside in planes roughly parallel to (011). In the crystal of (III), cations and anions also form columns parallel to the a axis, resulting in layers parallel to the (020) plane. Furthermore, the crystal structures of (I), (II) and (III) are consolidated by strong halogen (Br and/or I and/or Cl)⋯H and weak van der Waals inter­actions. In addition to the structural evaluation, a Hirshfeld surface analysis was carried out.

1. Chemical context

Halogenation is a chemical reaction that involves the introduction of one or more halogen atoms to an organic compound. Usually, either direct replacement of hydrogen by a halogen atom or addition of a halogen mol­ecule to double and triple bonds are used. The pathway and stereochemistry of halogenation reactions are strongly dependent on the halogenating agent. However, halogens and inter­halogens are very harmful to health. An effective source of active halogen should be a safe solid substance well soluble in different solvents, with a low pressure of halogen vapour and high content of the active halogen. As a source of halogens, mol­ecular complexes with N- and O-nucleophiles are widely used. However, the N-halogen succinimides slowly decompose when stored and are poorly soluble in some solvents, while the mol­ecular complexes of halogens with N- and O-nucleophiles (for instance, dioxane dibromide or complexes with pyridine) are short-lived (Abdell-Wahab et al., 1957 ▸; Horner et al., 1959 ▸; Zaugg et al., 1954 ▸; Buckles et al., 1957 ▸; Ramachandrappa et al., 1998 ▸; Groebel et al., 1960 ▸; Mohamed Farook et al., 2006 ▸; Sui et al., 2006 ▸). In this context, we synthesized inexpensive and readily available bis­(N,N-di­methyl­acetamide) hydrogen tri­halides as halogenation agents and source of positively charged halogen ions (Rodygin et al., 1992 ▸; Prokop’eva et al., 2008 ▸). The amide complexes with halogens are excellent reagents for the functionalization of phenols and anilines (Rodygin et al., 1992 ▸; Mikhailov et al., 1993 ▸; Safavora et al., 2019 ▸). They are also used in the synthesis of mono-halogen-substituted ketones (Rodygin et al., 1994a ▸; Burakov et al., 2001 ▸; Abdelhamid et al., 2011 ▸; Khalilov et al., 2021 ▸) and the halogenation of various alkenes, alkynes (Rodygin et al., 1994b ▸) and bridged ep­oxy-isoindolones (Zaytsev et al., 2017 ▸; Zubkov et al., 2018 ▸; Mertsalov et al., 2021a ▸,b ▸). The most famous amide complex, i.e. Povidone-iodine (PVP-I), also known as iodo­povidone, is an anti­septic used for skin disinfection before and after surgery (Stuart et al., 2009 ▸). Moreover, noncovalent inter­actions play critical roles in synthesis and catalysis, as well as in forming supra­molecular structures due to their significant contribution to the self-assembly process (Gurbanov et al., 2020a ▸,b ▸, 2022a ▸,b ▸; Ma et al., 2017 ▸, 2021 ▸; Mahmoudi et al., 2017a ▸,b ▸; Mahmudov et al., 2011 ▸, 2022 ▸). Similar to hydrogen bonding, the halogen bond has also been used in the design of materials (Shikhaliyev et al., 2019 ▸). We, thus, analyzed such expected respective inter­molecular inter­actions in the isolated and structurally characterized three title aggregates in the context of the present study.

2. Structural commentary

In the title compounds (I), (II) and (III) (Figs. 1 ▸, 2 ▸ and 3 ▸), the Br₃ ⁻, Br₂I⁻ and Cl₂I⁻ anions are almost or perfectly linear in geometry. For (I), Br1 resides in the centre of inversion symmetry [Br2—Br1—Br2(−x + 1, −y + 1, −z + 1) = 180.0°], with Br1—Br2 distances of 2.53725 (17) Å. The cations, except for their methyl H atoms, are essentially planar [r.m.s. deviation = 0.041 (1) Å for O1]. For (II), the angles and distances of the anion are Br1—I1—Br2 = 177.942 (5)°, I1—Br1 = 2.7244 (2) Å and I1—Br2 = 2.68597 (19) Å. These values are in agreement with data reported in the literature (Gardberg et al., 2002 ▸). The cations, except for their methyl H atoms, are again essentially planar [r.m.s. deviations = −0.018 (1) Å for O1 and −0.038 (2) Å for C7]. For (III), I1 resides in the centre of inversion symmetry [Cl1—I1—Cl1(−x + 1, −y + 1, −z + 1) = 180.0°], with distances of I1—Cl1 = 2.53973 (18) Å. The cations, except for their methyl H atoms, are planar and all reside on mirror planes.

Figure 1.

The mol­ecular structure of (I), with displacement ellipsoids for the non-H atoms drawn at the 50% probability level.

Figure 2.

The mol­ecular structure of (II), with displacement ellipsoids for the non-H atoms drawn at the 50% probability level. Symmetry codes: (_a) −x + 1, −y + 1, −z + 1; (_b) −x + 2, −y + 1, −z + 2.

Figure 3.

The mol­ecular structure of (III), with displacement ellipsoids for the non-H atoms drawn at the 50% probability level. Symmetry code: (_a) −x + 1, y, −z + 1.

In (I), (II) and (III), the O—C and N—C bond distances of the cation all fall between single and double bond values, with C1—N1 = 1.3134 (17) Å and C1—O1 = 1.2786 (16) Å for (I), C1—N1 = 1.3168 (16) Å, C5—N2 = 1.3121 (16) Å, C1—O1 = 1.2771 (15) Å and C5—O2 = 1.2794 (15) Å for (II), and C1—N1 = 1.3161 (8) Å and C1—O1 = 1.2750 (8) Å for (III). The corresponding bond lengths of the three compounds are in good agreement with each other and with the literature.

3. Supra­molecular features and Hirshfeld surface analysis

In the crystal of (I), the cations are linked by pairs of C—H⋯O hydrogen bonds (symmetry code: −x + 2, −y + 1, −z + 2), forming inversion dimers with an (8) ring motif (Bernstein et al., 1995 ▸) (Table 1 ▸ and Fig. 4 ▸). These dimers also exhibit O—H⋯O hydrogen bonds (symmetry code: −x + 2, −y + 1, −z + 2). Dimerized cation pairs and anions are arranged in columns along the a axis (Figs. 4 ▸ and 5 ▸). In the crystal of (II), two cations are refined in the asymmetric unit. These cations are linked by pairs of O—H⋯O and C—H⋯O hydrogen bonds, forming an (14) ring motif (Table 2 ▸, and Figs. 6 ▸ and 7 ▸). The groups of cations and anions form columns along the a axis and reside in planes parallel to (011) (Figs. 6 ▸ and 7 ▸). In the crystal of (III), cations and anions are arranged in columns parallel to the a axis, forming layers parallel to the (020) plane (Table 3 ▸, and Figs. 8 ▸ and 9 ▸). Furthermore, the crystal structures of (I), (II) and (III) are consolidated by strong halogen (Br and/or I and/or Cl)⋯H bonding inter­actions, Coulombic attraction and weak van der Waals inter­actions (Tables 4 ▸ and 5 ▸) between the cations and anions in three dimensions.

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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2A⋯O1i	0.98	2.52	3.2622 (18)	132
C2—H2B⋯Br2ii	0.98	3.14	4.0788 (15)	162
C2—H2C⋯Br1iii	0.98	3.13	3.9596 (14)	143
C3—H3A⋯Br2iv	0.98	3.10	4.0216 (15)	158
C3—H3C⋯Br2	0.98	3.05	3.8847 (15)	143
O1—H1⋯O1i	1.21	1.21	2.4224 (15)	180

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) .

Figure 4.

A view along the a axis of the O—H⋯O and C—H⋯O inter­actions in the crystal structure of (I).

Figure 5.

A view along the c axis of the O—H⋯O and C—H⋯O inter­actions in the crystal structure of (I).

Table 2. Hydrogen-bond geometry (Å, °) for (II) .

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯O2	0.75 (5)	1.69 (5)	2.4278 (13)	173 (4)
O2—H2⋯O1	0.85 (5)	1.59 (5)	2.4278 (14)	170 (4)
C2—H2A⋯O2	0.98	2.57	3.2872 (17)	130
C2—H2B⋯Br2	0.98	3.09	4.0105 (14)	158
C2—H2C⋯I1i	0.98	3.18	4.0838 (14)	155
C3—H3A⋯Br2ii	0.98	3.07	3.8153 (14)	134
C3—H3B⋯O2iii	0.98	2.54	3.3481 (16)	140
C4—H4A⋯I1i	0.98	3.31	4.1081 (14)	140
C6—H6A⋯O1	0.98	2.64	3.3630 (16)	131
C6—H6C⋯Br1ii	0.98	3.06	3.7331 (14)	128
C7—H7B⋯Br1iv	0.98	2.97	3.8980 (15)	159
C8—H8A⋯Br1v	0.98	3.05	3.9722 (15)	157

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

Figure 6.

A view along the a axis of the O—H⋯O and C—H⋯O inter­actions in the crystal structure of (II).

Figure 7.

A view along the b axis of the O—H⋯O and C—H⋯O inter­actions in the crystal structure of (II).

Table 3. Hydrogen-bond geometry (Å, °) for (III) .

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯O1i	0.64 (3)	1.79 (3)	2.4261 (11)	170 (4)
C2—H2A⋯Cl1ii	0.98	2.93	3.7461 (8)	141
C2—H2A⋯O1i	0.98	2.61	3.3230 (9)	130
C2—H2C⋯Cl1	0.98	2.96	3.6902 (3)	132
C3—H3A⋯Cl1iii	0.98	2.95	3.6479 (9)	129
C3—H3B⋯Cl1iv	0.98	2.89	3.7897 (8)	153
C3—H3C⋯O1v	0.98	2.65	3.6256 (4)	176

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

Figure 8.

A view along the a axis of the O—H⋯O inter­actions in the crystal structure of (III).

Figure 9.

A view along the c axis of the O—H⋯O inter­actions in the crystal structure of (III).

Table 4. Summary of short inter­atomic contacts (Å) in (I), (II) and (III).

Contact	Distance	Symmetry operation
(I)
H1⋯O1	1.61	−x + 2, −y + 1, −z + 2
O1⋯H4B	2.73	x +  , −y +  , z +
C2⋯H4C	3.06	−x +  , y +  , −z +
C2⋯H3B	3.09	x +  , −y +  , z −
H2A⋯Br2	3.21	x + 1, y, z
H3C⋯Br2	3.05	x, y, z
H2C⋯Br1	3.13	−x +  , y −  , −z +
H3A⋯Br2	3.09	−x + 1, −y + 1, −z + 2
H4C⋯Br2	3.23	−x +  , y −  , −z +
Br2⋯H2B	3.14	−x + 1, −y + 1, −z + 1
(II)
H1⋯H2	0.86	x, y, z
C1⋯O1	3.24	−x, −y + 1, −z + 1
H3C⋯O1	2.68	−x + 1, −y + 1, −z + 1
H2A⋯H2A	2.54	−x, −y, −z + 1
H3C⋯Br2	3.23	x, y + 1, z
H2B⋯Br2	3.09	x, y, z
H2C⋯I1	3.18	x − 1, y, z
H3A⋯Br2	3.07	−x + 1, −y + 1, −z + 1
H3C⋯H6A	2.58	−x + 1, −y + 1, −z + 1
O2⋯H3B	2.54	−x, −y + 1, −z + 1
H8B⋯Br1	3.19	−x + 1, −y, −z + 1
H6C⋯Br1	3.06	−x + 1, −y + 1, −z + 1
H8A⋯Br1	3.05	x, y, z + 1
H7B⋯Br1	2.97	x − 1, y, z + 1
(III)
H1⋯O1	1.79	−x + 1, y, −z + 2
H3C⋯O1	2.65	−x +  , y −  , −z + 2
H4B⋯Cl1	3.00	x, y − 1, z
H2C⋯Cl1	2.96	x, y, z
C3⋯C3	2.60	−x + 2, y, −z + 2
H3A⋯Cl1	2.95	−x +  , y −  , −z + 2
H2A⋯Cl1	2.93	x −  , y −  , z
H2C⋯H4C	2.58	x −  , y +  , z
H3B⋯Cl1	2.89	x +  , y −  , z
I1⋯H4A	3.37	−x + 1, y, −z + 1
I1⋯H4C	3.36	−x +  , y +  , −z + 1

Table 5. Percentage contributions of inter­atomic contacts to the Hirshfeld surface for (I), (II) and (III).

Contact	(I) (%)	(II) (%)	(III) (%)
H⋯H	57.5	60.3	88.9
Br⋯H/H⋯Br	24.0	15.2	–
O⋯H/H⋯O	13.3	12.0	6.5
C⋯H/H⋯C	3.0	2.7	2.0
Br⋯N/N⋯Br	1.0	–	–
N⋯H/H⋯N	0.9	2.4	0.8
Br⋯C/C⋯Br	0.5	–	–
I⋯H/H⋯I	–	4.7	–
O⋯C/C⋯O	–	2.2	–
O⋯N/N⋯O	–	0.3	–
O⋯O	–	0.1	–
Cl⋯N/N⋯Cl	–	–	0.8
Cl⋯C/C⋯Cl	–	–	0.7
Cl⋯H/H⋯Cl	–	–	0.4

The O⋯O distances in (I), (II) and (III) are 2.4224 (15), 2.4278 (14) and 2.4261 (9) Å, respectivly, and are thereby within the range (2.31–2.63 Å) found for short/strong classical hydrogen bonds (Hussain & Schlemper, 1980 ▸; Behmel et al., 1981 ▸).

The Hirshfeld surface analysis and the associated two-dimensional fingerprint plots over the cations of (I), (II) and (III) were carried out and created with CrystalExplorer17.5 (Spackman et al., 2021 ▸). A summary of the short inter­atomic contacts in (I), (II) and (III) is given in Table 4 ▸. The two-dimensional fingerprint plots for compounds (I), (II) and (III) are shown in Fig. 10 ▸. The principal inter­atomic inter­actions for the title compound [Figs. 10 ▸(b)–(d) and Table 5 ▸] are delineated into H⋯H [57.5% for (I); 60.3% for (II); 88.9% for (III)], Br⋯H/H⋯Br [24.0% for (I); 15.2% for (II)], O⋯H/H⋯O [6.5% for (III)] and O⋯H/H⋯O [13.3% for (I); 12.0% for (II)] and C⋯H/H⋯C [2.0% for (III)] contacts.

Figure 10.

A view of the two-dimensional fingerprint plots for compounds (I), (II) and (III), showing (a) all inter­actions, and separated into (b) H⋯H, (c) Br⋯H/H⋯Br for (I) and (II), O⋯H/H⋯O for (III) and (d) O⋯H/H⋯O for (I) and (II), C⋯H/H⋯C for (III) inter­actions. The d _i and d _e values are the closest inter­nal and external distances (in Å) from given points on the Hirshfeld surface contacts.

The respective differences in the crystal structures of the three title compounds [(I): space group, monoclinic P2₁/n, Z = 2; (II): space group, triclinic P , Z = 2; (III): space group, monoclinic C2/m, Z = 2], may be the result of small deviations in the inter­actions arising from the different crystal systems and packing, as well as from the variations in the anions of the compounds.

4. Database survey

A database search was carried out using ConQUEST (Bruno et al., 2002 ▸), part of Version 2022.3.0 of the Cambridge Structural Database (Groom et al., 2016 ▸). A search for structures with the simultaneous presence of N,N-di­methyl­acetamide and its respective protonated form resulted in ten hits. Two compounds are deposited twice, so there are only eight related structures known. Compounds closely related to the title compound are: bis­[hexa­kis­(N,N-di­methyl­acetamide-κO)aluminium(III)] bis­(N,N-di­methyl­acetamide)­ium hepta­kis­(perchlorate) (CSD refcode DEGBOH; Suzuki & Ishiguro, 2006 ▸), hydrogen bis­(N,N-di­methyl­acetamide) tetra­chloro­gold(III) (HDMAAU; Hussain et al., 1980 ▸), hydrogen bis­(di­methyl­acetamide) tribromide [SEGMOG (Gubin et al., 1988 ▸) and SEGMOG01 (Mikhailov et al., 1992 ▸)].

In the crystal of DEGBOH (space group: monoclinic P2₁ n, Z = 2), the Al³⁺ ion is surrounded by dma mol­ecules (dma = di­methyl­acetamide) in an octa­hedral arrangement. The dma mol­ecules are essentially planar. Three Al—O—C—N torsion angles [138.8 (8)–149.3 (4)°] are found to deviate significantly from 180°. The centrosymmetric cation has the bridging H atom at the centre of inversion. The planar structure is essentially the same as those reported for [H(dma)₂]⁺ cations; the O⋯O distance [2.386 (8) Å] is within the range (2.31–2.63 Å) found for short hydrogen bonds (Hussain & Schlemper, 1980 ▸; Behmel et al., 1981 ▸).

In the crystal of HDMAAU (space group: monoclinic P2₁ a, Z = 2), the structure consists of distinct [AuCl₄]⁻ anions and [H(dma)₂]⁺ cations, with the gold and the bridging H atoms located at centres of symmetry. The hydrogen bond is ‘symmetrical’ as a result of crystallographic requirements. The O⋯O distance is 2.430 (16) Å. Thermal motion analysis indicates that methyl groups attached to nitro­gen have higher rotational amplitudes, resulting in short apparent C—H bond lengths [average 0.96 (4) Å] compared with the methyl group attached to a carbonyl C atom which has an average C—H bond length of 1.02 (2) Å.

In the crystal of SEGMOG (space group: monoclinic P2₁ c, Z = 2), two N,N-di­methyl­acetamide mol­ecules in the asymmetric unit are connected to each other by an O—H⋯O hydrogen bond, essentially sharing the central H atom. These mol­ecules and the Br—Br—Br groups are arranged in columns parallel to the a axis. The arrangement is consolidated in the crystal packing by van der Waals inter­actions between these columns.

In the crystal of SEGMOG01 (space group: monoclinic P2₁ n, Z = 2), the unit-cell parameters and the arrangement of the mol­ecules are relatively similar to the older structure (SEGMOG), while the H atom bridging the the two acetamides was not refined.

5. Synthesis and crystallization

5.1. General procedure

To a solution of di­methyl­acetamide (9.28 ml, 0.1 mol) in 0.09 mol of 38% hydro­chloric or 40% hydro­bromic acid under stirring and cooling in an ice–water bath, 0.05 mol iodine monochloride (8.10 g, 0.05 mol), iodine monobromide (10.35 g, 0.05 mol) or bromine (4.00 g, 0.05 mol) was added gradually. The mixture was stirred for 1 h and the crystals were filtered off, dried and recrystallized from methanol to give the target bis­(N,N-di­methyl­acetamide) hydrogen halides as orange colored solids. Single crystals of bis­(N,N-di­methyl­acetamide) hydrogen halides were obtained by slow crystallization from methanol.

5.2. N,N-Di­methyl­acetamide–1-(dimethyl-λ⁴-aza­nyl­idene)ethan-1-ol tribromide (1/1), (I)

Bright orange crystals (Rodygin et al., 1992 ▸; Gubin et al., 1988 ▸), yield 81% (16.8 g), m.p. 361–362 K. IR (KBr), ν (cm⁻¹): 1664 (NCO). ¹H NMR (700.2 MHz, CDCl₃): δ (J, Hz) 12.51 (br s, 1H), 3.28 (s, 3H, NCH₃), 3.19 (s, 3H, NCH₃), 2.45 (s, 3H, CH₃); ¹³C{¹H} NMR (176 MHz, CDCl₃): δ 174.5, 39.7, 37.5, 19.9.

5.3. N,N-Di­methyl­acetamide–1-(dimethyl-λ⁴-aza­nyl­idene)ethan-1-ol di­bromido­iodate (1/1), (II)

Bright-orange crystals, yield 44% (10.2 g), m.p. 343–344 K. IR (KBr), ν (cm⁻¹): 1606 (NCO). ¹H NMR (700.2 MHz, CDCl₃): δ (J, Hz) 10.72 (br s, 1H), 3.28 (s, 3H, NCH₃), 3.19 (s, 3H, NCH₃), 2.46 (s, 3H, CH₃); ¹³C{¹H} NMR (176 MHz, CDCl₃): δ 174.6, 39.6, 37.5, 20.1.

5.4. N,N-Di­methyl­acetamide–1-(dimethyl-λ⁴-aza­nyl­idene)ethan-1-ol di­chlorido­iodate (1/1), (III)

Bright orange crystals, yield 75% (14 g), m.p. 364–365 K. IR (KBr), ν (cm⁻¹): 1611 (NCO). ¹H NMR (700.2 MHz, CDCl₃): δ (J, Hz) 9.98 (br s, 1H), 3.25 (s, 3H, NCH₃), 3.17 (s, 3H, NCH₃), 2.41 (s, 3H, CH₃); ¹³C{¹H} NMR (176 MHz, CDCl₃): δ 174.2, 39.4, 37.2, 19.8.

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 6 ▸. In compounds (I), (II) and (III), the C-bound H atoms were positioned geometrically, with C—H = 0.98 Å (for methyl H atoms), and constrained to ride on their parent atoms, with U _iso(H) = 1.5U _eq(C). The hy­droxy H atoms were found in the difference Fourier maps and their coordinates were refined freely, with U _iso(H) = 1.5U _eq(O). In (I), the H atom of the OH group is located in a special position (1.0, 0.5, 1.0) with an occupancy of 0.5 for the rrefined atom. In (II), the H atoms of the OH groups are disordered over two positions, with occupancies of 0.49 and 0.51. In (III), the H atom of the OH group was refined with an occupancy of 0.25 for its position close to an inversion centre in between the O atoms of two acetamides and simultaneously residing on a mirror plane.

Table 6. Experimental details.

For all structures: Z = 2. Experiments were carried out at 100 K with Mo Kα radiation using a Bruker Kappa APEXII area-detector diffractometer. Absorption was corrected for by multi-scan methods (SADABS; Bruker, 2008 ▸).

	(I)	(II)	(III)
Crystal data
Chemical formula	C4H9NO·C4H10NO+·Br3 −	C4H9NO·C4H10NO+·Br2I−	C4H9NO·C4H10NO+·Cl2I−
M r	414.98	461.97	373.05
Crystal system, space group	Monoclinic, P21/n	Triclinic, P	Monoclinic, C2/m
a, b, c (Å)	7.9009 (4), 10.3466 (6), 9.4948 (5)	7.2943 (3), 7.9544 (4), 13.6097 (7)	10.5264 (3), 6.7261 (2), 10.8124 (3)
α, β, γ (°)	90, 107.703 (2), 90	90.645 (2), 103.651 (2), 93.656 (2)	90, 105.950 (1), 90
V (Å3)	739.42 (7)	765.51 (6)	736.06 (4)
μ (mm−1)	8.17	7.30	2.53
Crystal size (mm)	0.24 × 0.20 × 0.14	0.14 × 0.08 × 0.06	0.20 × 0.18 × 0.14
Data collection
T min, T max	0.315, 0.394	0.515, 0.669	0.630, 0.719
No. of measured, independent and observed [I > 2σ(I)] reflections	11995, 3239, 2402	30601, 6766, 5446	13071, 1745, 1745
R int	0.026	0.021	0.014
(sin θ/λ)max (Å−1)	0.807	0.811	0.811
Refinement
R[F 2 > 2σ(F 2)], wR(F 2), S	0.025, 0.056, 1.01	0.019, 0.038, 1.03	0.008, 0.022, 1.06
No. of reflections	3239	6766	1745
No. of parameters	73	149	52
H-atom treatment	H-atom parameters constrained	H atoms treated by a mixture of independent and constrained refinement	H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)	0.43, −0.78	0.52, −0.62	0.46, −0.26

Computer programs: APEX2 and SAINT (Bruker, 2013 ▸), SHELXT (Sheldrick, 2015a ▸), SHELXL (Sheldrick, 2015b ▸), ORTEP-3 for Windows (Farrugia, 2012 ▸) and PLATON (Spek, 2020 ▸).

Supplementary Material

CCDC references: 2271693, 2271692, 2271691

Additional supporting information: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol tribromide (1/1) (I) . Crystal data

C4H9NO·C4H10NO+·Br3−	F(000) = 404
Mr = 414.98	Dx = 1.864 Mg m−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
a = 7.9009 (4) Å	Cell parameters from 3187 reflections
b = 10.3466 (6) Å	θ = 3.0–34.7°
c = 9.4948 (5) Å	µ = 8.17 mm−1
β = 107.703 (2)°	T = 100 K
V = 739.42 (7) Å3	Fragment, orange
Z = 2	0.24 × 0.20 × 0.14 mm

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol tribromide (1/1) (I) . Data collection

Bruker Kappa APEXII area-detector diffractometer	2402 reflections with I > 2σ(I)
ω– and φ–scans	Rint = 0.026
Absorption correction: multi-scan (SADABS; Bruker, 2008)	θmax = 35.0°, θmin = 4.5°
Tmin = 0.315, Tmax = 0.394	h = −12→12
11995 measured reflections	k = −16→16
3239 independent reflections	l = −15→15

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol tribromide (1/1) (I) . Refinement

Refinement on F2	Primary atom site location: dual
Least-squares matrix: full	Hydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.025	H-atom parameters constrained
wR(F2) = 0.056	w = 1/[σ2(Fo2) + (0.0249P)2 + 0.0334P] where P = (Fo2 + 2Fc2)/3
S = 1.01	(Δ/σ)max = 0.002
3239 reflections	Δρmax = 0.43 e Å−3
73 parameters	Δρmin = −0.78 e Å−3
0 restraints

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol tribromide (1/1) (I) . Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol tribromide (1/1) (I) . Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Br1	0.500000	0.500000	0.500000	0.01461 (5)
Br2	0.26135 (2)	0.50973 (2)	0.62805 (2)	0.02228 (5)
O1	0.85472 (13)	0.45244 (10)	0.98120 (11)	0.0190 (2)
H1	1.000000	0.500000	1.000000	0.029*
N1	0.66034 (15)	0.29961 (10)	0.87188 (13)	0.0153 (2)
C1	0.80749 (18)	0.36364 (12)	0.88341 (15)	0.0146 (2)
C2	0.91855 (19)	0.33325 (14)	0.78479 (16)	0.0193 (3)
H2A	1.028724	0.383619	0.816158	0.029*
H2B	0.852428	0.355410	0.682486	0.029*
H2C	0.947123	0.240846	0.791228	0.029*
C3	0.55467 (19)	0.32410 (14)	0.97137 (17)	0.0198 (3)
H3A	0.624789	0.374837	1.056242	0.030*
H3B	0.521000	0.241642	1.006057	0.030*
H3C	0.447312	0.372248	0.918561	0.030*
C4	0.5868 (2)	0.20268 (14)	0.75764 (17)	0.0214 (3)
H4A	0.658131	0.199738	0.689389	0.032*
H4B	0.464005	0.225520	0.703018	0.032*
H4C	0.589038	0.117778	0.803936	0.032*

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol tribromide (1/1) (I) . Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Br1	0.01420 (9)	0.01516 (8)	0.01360 (8)	0.00133 (6)	0.00293 (7)	−0.00072 (6)
Br2	0.01914 (8)	0.02903 (8)	0.02132 (8)	0.00196 (6)	0.01013 (6)	−0.00041 (6)
O1	0.0217 (5)	0.0179 (4)	0.0149 (5)	−0.0066 (4)	0.0018 (4)	−0.0020 (4)
N1	0.0183 (6)	0.0141 (5)	0.0135 (5)	−0.0035 (4)	0.0050 (5)	−0.0023 (4)
C1	0.0168 (6)	0.0132 (5)	0.0116 (6)	0.0002 (5)	0.0009 (5)	0.0037 (4)
C2	0.0210 (7)	0.0196 (6)	0.0184 (7)	−0.0002 (5)	0.0078 (6)	0.0016 (5)
C3	0.0205 (7)	0.0214 (6)	0.0200 (7)	−0.0025 (5)	0.0098 (6)	−0.0021 (5)
C4	0.0255 (7)	0.0186 (6)	0.0191 (7)	−0.0073 (5)	0.0056 (6)	−0.0063 (5)

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol tribromide (1/1) (I) . Geometric parameters (Å, º)

Br1—Br2i	2.5372 (2)	C2—H2B	0.9800
Br1—Br2	2.5372 (2)	C2—H2C	0.9800
O1—C1	1.2786 (16)	C3—H3A	0.9800
O1—H1	1.2112	C3—H3B	0.9800
N1—C1	1.3134 (17)	C3—H3C	0.9800
N1—C3	1.4605 (18)	C4—H4A	0.9800
N1—C4	1.4618 (18)	C4—H4B	0.9800
C1—C2	1.4984 (19)	C4—H4C	0.9800
C2—H2A	0.9800
Br2i—Br1—Br2	180.0	H2B—C2—H2C	109.5
C1—O1—H1	116.95	N1—C3—H3A	109.5
C1—N1—C3	121.62 (11)	N1—C3—H3B	109.5
C1—N1—C4	123.36 (12)	H3A—C3—H3B	109.5
C3—N1—C4	115.00 (11)	N1—C3—H3C	109.5
O1—C1—N1	118.58 (12)	H3A—C3—H3C	109.5
O1—C1—C2	120.50 (12)	H3B—C3—H3C	109.5
N1—C1—C2	120.92 (12)	N1—C4—H4A	109.5
C1—C2—H2A	109.5	N1—C4—H4B	109.5
C1—C2—H2B	109.5	H4A—C4—H4B	109.5
H2A—C2—H2B	109.5	N1—C4—H4C	109.5
C1—C2—H2C	109.5	H4A—C4—H4C	109.5
H2A—C2—H2C	109.5	H4B—C4—H4C	109.5
C3—N1—C1—O1	−2.46 (19)	C3—N1—C1—C2	177.27 (12)
C4—N1—C1—O1	175.52 (13)	C4—N1—C1—C2	−4.8 (2)

Symmetry code: (i) −x+1, −y+1, −z+1.

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol tribromide (1/1) (I) . Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2A···O1ii	0.98	2.52	3.2622 (18)	132
C2—H2B···Br2i	0.98	3.14	4.0788 (15)	162
C2—H2C···Br1iii	0.98	3.13	3.9596 (14)	143
C3—H3A···Br2iv	0.98	3.10	4.0216 (15)	158
C3—H3C···Br2	0.98	3.05	3.8847 (15)	143
O1—H1···O1ii	1.21	1.21	2.4224 (15)	180
C3—H3A···O1	0.98	2.29	2.6940 (19)	104

Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) −x+2, −y+1, −z+2; (iii) −x+3/2, y−1/2, −z+3/2; (iv) −x+1, −y+1, −z+2.

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol dibromidoiodate (1/1) (II) . Crystal data

C4H9NO·C4H10NO−·Br2I−	Z = 2
Mr = 461.97	F(000) = 440
Triclinic, P1	Dx = 2.004 Mg m−3
a = 7.2943 (3) Å	Mo Kα radiation, λ = 0.71073 Å
b = 7.9544 (4) Å	Cell parameters from 9984 reflections
c = 13.6097 (7) Å	θ = 2.9–35.2°
α = 90.645 (2)°	µ = 7.30 mm−1
β = 103.651 (2)°	T = 100 K
γ = 93.656 (2)°	Fragment, orange
V = 765.51 (6) Å3	0.14 × 0.08 × 0.06 mm

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol dibromidoiodate (1/1) (II) . Data collection

Bruker Kappa APEXII area-detector diffractometer	5446 reflections with I > 2σ(I)
ω– and φ–scans	Rint = 0.021
Absorption correction: multi-scan (SADABS; Bruker, 2008)	θmax = 35.2°, θmin = 4.3°
Tmin = 0.515, Tmax = 0.669	h = −11→11
30601 measured reflections	k = −12→12
6766 independent reflections	l = −22→21

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol dibromidoiodate (1/1) (II) . Refinement

Refinement on F2	Primary atom site location: dual
Least-squares matrix: full	Hydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.019	H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.038	w = 1/[σ2(Fo2) + (0.0119P)2 + 0.2374P] where P = (Fo2 + 2Fc2)/3
S = 1.03	(Δ/σ)max = 0.001
6766 reflections	Δρmax = 0.52 e Å−3
149 parameters	Δρmin = −0.62 e Å−3
0 restraints

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol dibromidoiodate (1/1) (II) . Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol dibromidoiodate (1/1) (II) . Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq	Occ. (<1)
I1	0.65027 (2)	0.18015 (2)	0.21358 (2)	0.01710 (2)
Br1	0.80118 (2)	0.33097 (2)	0.06912 (2)	0.02346 (3)
Br2	0.51412 (2)	0.02963 (2)	0.35979 (2)	0.02157 (3)
O1	0.20994 (14)	0.43799 (12)	0.57436 (7)	0.01964 (19)
H1	0.187 (6)	0.388 (6)	0.617 (3)	0.029*	0.49 (4)
O2	0.10583 (13)	0.27819 (13)	0.70454 (7)	0.02121 (19)
H2	0.151 (5)	0.325 (6)	0.659 (3)	0.032*	0.51 (4)
N1	0.22672 (15)	0.45877 (13)	0.41323 (8)	0.01563 (19)
N2	0.14789 (15)	0.19762 (14)	0.86403 (8)	0.0168 (2)
C1	0.17805 (16)	0.37110 (15)	0.48569 (9)	0.0147 (2)
C2	0.08734 (19)	0.19621 (16)	0.46499 (10)	0.0204 (2)
H2A	0.080500	0.143984	0.529020	0.031*
H2B	0.162652	0.129403	0.430349	0.031*
H2C	−0.040553	0.200696	0.422060	0.031*
C3	0.31786 (18)	0.62905 (16)	0.43360 (10)	0.0198 (2)
H3A	0.354648	0.651700	0.506798	0.030*
H3B	0.229380	0.711180	0.401612	0.030*
H3C	0.430563	0.638270	0.406042	0.030*
C4	0.1909 (2)	0.39725 (18)	0.30812 (10)	0.0215 (3)
H4A	0.104320	0.295852	0.298507	0.032*
H4B	0.310488	0.370162	0.292695	0.032*
H4C	0.134030	0.484580	0.262824	0.032*
C5	0.21588 (17)	0.26890 (15)	0.79243 (9)	0.0155 (2)
C6	0.41829 (18)	0.33486 (16)	0.81159 (10)	0.0192 (2)
H6A	0.438604	0.396328	0.752644	0.029*
H6B	0.500151	0.240498	0.823484	0.029*
H6C	0.448650	0.410935	0.871198	0.029*
C7	−0.0468 (2)	0.12246 (19)	0.84285 (11)	0.0243 (3)
H7A	−0.107738	0.135459	0.771288	0.036*
H7B	−0.117410	0.179306	0.884927	0.036*
H7C	−0.045456	0.002396	0.858179	0.036*
C8	0.2581 (2)	0.18213 (19)	0.96814 (10)	0.0236 (3)
H8A	0.382190	0.242901	0.976432	0.035*
H8B	0.274782	0.062886	0.982492	0.035*
H8C	0.191026	0.230260	1.015097	0.035*

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol dibromidoiodate (1/1) (II) . Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
I1	0.01763 (4)	0.01708 (3)	0.01549 (4)	0.00366 (3)	0.00121 (3)	−0.00183 (3)
Br1	0.02527 (7)	0.02855 (7)	0.01748 (7)	0.00332 (5)	0.00655 (5)	−0.00017 (5)
Br2	0.02328 (7)	0.01921 (6)	0.02211 (7)	0.00054 (5)	0.00536 (5)	0.00173 (5)
O1	0.0235 (5)	0.0221 (4)	0.0133 (4)	0.0003 (4)	0.0045 (4)	0.0014 (3)
O2	0.0171 (4)	0.0323 (5)	0.0145 (4)	0.0026 (4)	0.0038 (4)	0.0061 (4)
N1	0.0139 (5)	0.0185 (4)	0.0143 (5)	0.0007 (4)	0.0031 (4)	0.0021 (4)
N2	0.0175 (5)	0.0207 (5)	0.0125 (5)	0.0015 (4)	0.0040 (4)	0.0017 (4)
C1	0.0113 (5)	0.0178 (5)	0.0146 (5)	0.0026 (4)	0.0020 (4)	0.0022 (4)
C2	0.0220 (6)	0.0181 (5)	0.0202 (6)	−0.0019 (5)	0.0039 (5)	0.0016 (5)
C3	0.0168 (6)	0.0189 (5)	0.0227 (6)	−0.0016 (4)	0.0030 (5)	0.0038 (5)
C4	0.0237 (7)	0.0266 (6)	0.0148 (6)	0.0022 (5)	0.0059 (5)	0.0006 (5)
C5	0.0164 (5)	0.0161 (5)	0.0149 (5)	0.0043 (4)	0.0047 (4)	0.0006 (4)
C6	0.0182 (6)	0.0213 (5)	0.0180 (6)	0.0003 (4)	0.0043 (5)	0.0013 (5)
C7	0.0194 (6)	0.0337 (7)	0.0208 (7)	−0.0019 (5)	0.0075 (5)	0.0031 (5)
C8	0.0270 (7)	0.0292 (7)	0.0133 (6)	0.0001 (5)	0.0027 (5)	0.0039 (5)

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol dibromidoiodate (1/1) (II) . Geometric parameters (Å, º)

I1—Br2	2.6860 (2)	C3—H3A	0.9800
I1—Br1	2.7243 (2)	C3—H3B	0.9800
O1—C1	1.2771 (15)	C3—H3C	0.9800
O1—H1	0.75 (5)	C4—H4A	0.9800
O2—C5	1.2794 (15)	C4—H4B	0.9800
O2—H2	0.85 (5)	C4—H4C	0.9800
N1—C1	1.3168 (16)	C5—C6	1.4965 (18)
N1—C3	1.4640 (16)	C6—H6A	0.9800
N1—C4	1.4648 (17)	C6—H6B	0.9800
N2—C5	1.3121 (16)	C6—H6C	0.9800
N2—C8	1.4656 (17)	C7—H7A	0.9800
N2—C7	1.4673 (17)	C7—H7B	0.9800
C1—C2	1.4961 (17)	C7—H7C	0.9800
C2—H2A	0.9800	C8—H8A	0.9800
C2—H2B	0.9800	C8—H8B	0.9800
C2—H2C	0.9800	C8—H8C	0.9800
Br2—I1—Br1	177.942 (6)	H4A—C4—H4B	109.5
C1—O1—H1	120 (3)	N1—C4—H4C	109.5
C5—O2—H2	118 (3)	H4A—C4—H4C	109.5
C1—N1—C3	120.94 (11)	H4B—C4—H4C	109.5
C1—N1—C4	123.49 (11)	O2—C5—N2	118.46 (12)
C3—N1—C4	115.55 (10)	O2—C5—C6	120.28 (11)
C5—N2—C8	123.75 (11)	N2—C5—C6	121.25 (11)
C5—N2—C7	120.94 (11)	C5—C6—H6A	109.5
C8—N2—C7	115.28 (11)	C5—C6—H6B	109.5
O1—C1—N1	118.77 (11)	H6A—C6—H6B	109.5
O1—C1—C2	120.38 (11)	C5—C6—H6C	109.5
N1—C1—C2	120.84 (11)	H6A—C6—H6C	109.5
C1—C2—H2A	109.5	H6B—C6—H6C	109.5
C1—C2—H2B	109.5	N2—C7—H7A	109.5
H2A—C2—H2B	109.5	N2—C7—H7B	109.5
C1—C2—H2C	109.5	H7A—C7—H7B	109.5
H2A—C2—H2C	109.5	N2—C7—H7C	109.5
H2B—C2—H2C	109.5	H7A—C7—H7C	109.5
N1—C3—H3A	109.5	H7B—C7—H7C	109.5
N1—C3—H3B	109.5	N2—C8—H8A	109.5
H3A—C3—H3B	109.5	N2—C8—H8B	109.5
N1—C3—H3C	109.5	H8A—C8—H8B	109.5
H3A—C3—H3C	109.5	N2—C8—H8C	109.5
H3B—C3—H3C	109.5	H8A—C8—H8C	109.5
N1—C4—H4A	109.5	H8B—C8—H8C	109.5
N1—C4—H4B	109.5
C3—N1—C1—O1	0.75 (17)	C8—N2—C5—O2	−178.76 (12)
C4—N1—C1—O1	−177.75 (11)	C7—N2—C5—O2	3.09 (18)
C3—N1—C1—C2	−179.15 (11)	C8—N2—C5—C6	2.56 (19)
C4—N1—C1—C2	2.35 (18)	C7—N2—C5—C6	−175.59 (12)

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol dibromidoiodate (1/1) (II) . Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O2	0.75 (5)	1.69 (5)	2.4278 (13)	173 (4)
O2—H2···O1	0.85 (5)	1.59 (5)	2.4278 (14)	170 (4)
C2—H2A···O2	0.98	2.57	3.2872 (17)	130
C2—H2B···Br2	0.98	3.09	4.0105 (14)	158
C2—H2C···I1i	0.98	3.18	4.0838 (14)	155
C3—H3A···Br2ii	0.98	3.07	3.8153 (14)	134
C3—H3B···O2iii	0.98	2.54	3.3481 (16)	140
C4—H4A···I1i	0.98	3.31	4.1081 (14)	140
C6—H6A···O1	0.98	2.64	3.3630 (16)	131
C6—H6C···Br1ii	0.98	3.06	3.7331 (14)	128
C7—H7B···Br1iv	0.98	2.97	3.8980 (15)	159
C8—H8A···Br1v	0.98	3.05	3.9722 (15)	157
C3—H3A···O1	0.98	2.26	2.6878 (16)	105
C7—H7A···O2	0.98	2.24	2.6801 (18)	106

Symmetry codes: (i) x−1, y, z; (ii) −x+1, −y+1, −z+1; (iii) −x, −y+1, −z+1; (iv) x−1, y, z+1; (v) x, y, z+1.

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol dichloridoiodate (1/1) (III) . Crystal data

C4H9NO·C4H10NO−·Cl2I−	F(000) = 368
Mr = 373.05	Dx = 1.683 Mg m−3
Monoclinic, C2/m	Mo Kα radiation, λ = 0.71073 Å
a = 10.5264 (3) Å	Cell parameters from 9986 reflections
b = 6.7261 (2) Å	θ = 3.6–35.1°
c = 10.8124 (3) Å	µ = 2.53 mm−1
β = 105.950 (1)°	T = 100 K
V = 736.06 (4) Å3	Fragment, orange
Z = 2	0.20 × 0.18 × 0.14 mm

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol dichloridoiodate (1/1) (III) . Data collection

Bruker Kappa APEXII area-detector diffractometer	1745 reflections with I > 2σ(I)
ω– and φ–scans	Rint = 0.014
Absorption correction: multi-scan (SADABS; Bruker, 2008)	θmax = 35.2°, θmin = 4.4°
Tmin = 0.630, Tmax = 0.719	h = −16→16
13071 measured reflections	k = −10→10
1745 independent reflections	l = −17→16

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol dichloridoiodate (1/1) (III) . Refinement

Refinement on F2	Primary atom site location: dual
Least-squares matrix: full	Hydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.008	H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.022	w = 1/[σ2(Fo2) + (0.0153P)2 + 0.0381P] where P = (Fo2 + 2Fc2)/3
S = 1.06	(Δ/σ)max = 0.003
1745 reflections	Δρmax = 0.46 e Å−3
52 parameters	Δρmin = −0.25 e Å−3
0 restraints

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol dichloridoiodate (1/1) (III) . Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol dichloridoiodate (1/1) (III) . Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq	Occ. (<1)
I1	0.500000	0.500000	0.500000	0.01617 (2)
Cl1	0.60222 (2)	0.500000	0.74187 (2)	0.02093 (3)
O1	0.60066 (6)	0.000000	0.96603 (6)	0.02505 (10)
H1	0.543 (3)	0.000000	0.977 (3)	0.038*	0.5
N1	0.70175 (6)	0.000000	0.81090 (6)	0.01741 (9)
C1	0.59151 (7)	0.000000	0.84597 (6)	0.01742 (10)
C2	0.45979 (7)	0.000000	0.74807 (8)	0.02291 (12)
H2A	0.390193	−0.021971	0.790959	0.034*	0.5
H2B	0.457166	−0.106447	0.685527	0.034*	0.5
H2C	0.445707	0.128418	0.703565	0.034*	0.5
C3	0.82909 (8)	0.000000	0.90856 (8)	0.02547 (13)
H3A	0.824028	0.085866	0.980273	0.038*	0.5
H3B	0.897594	0.049926	0.870861	0.038*	0.5
H3C	0.851076	−0.135792	0.940046	0.038*	0.5
C4	0.70493 (8)	0.000000	0.67698 (7)	0.02212 (12)
H4A	0.622560	0.056849	0.623015	0.033*	0.5
H4B	0.714477	−0.136724	0.649508	0.033*	0.5
H4C	0.779897	0.079874	0.668365	0.033*	0.5

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol dichloridoiodate (1/1) (III) . Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
I1	0.01526 (3)	0.01688 (3)	0.01778 (3)	0.000	0.00693 (2)	0.000
Cl1	0.02127 (7)	0.02325 (7)	0.01802 (6)	0.000	0.00499 (5)	0.000
O1	0.0226 (2)	0.0357 (3)	0.0204 (2)	0.000	0.01195 (19)	0.000
N1	0.0170 (2)	0.0189 (2)	0.0187 (2)	0.000	0.00881 (18)	0.000
C1	0.0173 (2)	0.0164 (2)	0.0208 (2)	0.000	0.0090 (2)	0.000
C2	0.0176 (3)	0.0254 (3)	0.0260 (3)	0.000	0.0065 (2)	0.000
C3	0.0172 (3)	0.0356 (4)	0.0242 (3)	0.000	0.0067 (2)	0.000
C4	0.0235 (3)	0.0260 (3)	0.0201 (3)	0.000	0.0113 (2)	0.000

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol dichloridoiodate (1/1) (III) . Geometric parameters (Å, º)

I1—Cl1	2.5398 (2)	C2—H2Cii	0.980 (10)
I1—Cl1i	2.5398 (2)	C3—H3A	0.9800
O1—C1	1.2750 (8)	C3—H3B	0.9800
O1—H1	0.64 (3)	C3—H3C	0.9800
N1—C1	1.3161 (8)	C3—H3Aii	0.980 (9)
N1—C4	1.4576 (9)	C3—H3Bii	0.980 (6)
N1—C3	1.4608 (10)	C3—H3Cii	0.980 (3)
C1—C2	1.4955 (10)	C4—H4A	0.9800
C2—H2A	0.9800	C4—H4B	0.9800
C2—H2B	0.9800	C4—H4C	0.9800
C2—H2C	0.9800	C4—H4Aii	0.980 (7)
C2—H2Aii	0.980 (5)	C4—H4Bii	0.9800 (17)
C2—H2Bii	0.980 (15)	C4—H4Cii	0.980 (8)
Cl1—I1—Cl1i	180.0	H3A—C3—H3Aii	72.2
C1—O1—H1	112 (3)	H3B—C3—H3Aii	137.5
C1—N1—C4	123.30 (6)	H3C—C3—H3Aii	40.1
C1—N1—C3	119.89 (6)	N1—C3—H3Bii	109.47 (14)
C4—N1—C3	116.81 (6)	H3A—C3—H3Bii	137.5
O1—C1—N1	117.87 (7)	H3B—C3—H3Bii	40.1
O1—C1—C2	121.10 (6)	H3C—C3—H3Bii	72.2
N1—C1—C2	121.02 (6)	H3Aii—C3—H3Bii	109.5
C1—C2—H2A	109.5	N1—C3—H3Cii	109.47 (6)
C1—C2—H2B	109.5	H3A—C3—H3Cii	40.1
H2A—C2—H2B	109.5	H3B—C3—H3Cii	72.2
C1—C2—H2C	109.5	H3C—C3—H3Cii	137.5
H2A—C2—H2C	109.5	H3Aii—C3—H3Cii	109.5
H2B—C2—H2C	109.5	H3Bii—C3—H3Cii	109.5
C1—C2—H2Aii	109.47 (11)	N1—C4—H4A	109.5
H2B—C2—H2Aii	123.6	N1—C4—H4B	109.5
H2C—C2—H2Aii	93.9	H4A—C4—H4B	109.5
C1—C2—H2Bii	109.5 (3)	N1—C4—H4C	109.5
H2A—C2—H2Bii	123.6	H4A—C4—H4C	109.5
H2B—C2—H2Bii	93.9	H4B—C4—H4C	109.5
H2C—C2—H2Bii	17.3	N1—C4—H4Aii	109.47 (15)
H2Aii—C2—H2Bii	109.5	H4A—C4—H4Aii	45.9
C1—C2—H2Cii	109.5 (2)	H4B—C4—H4Aii	66.5
H2A—C2—H2Cii	93.9	H4C—C4—H4Aii	139.6
H2B—C2—H2Cii	17.3	N1—C4—H4Bii	109.47 (3)
H2C—C2—H2Cii	123.6	H4A—C4—H4Bii	66.5
H2Aii—C2—H2Cii	109.5	H4B—C4—H4Bii	139.6
H2Bii—C2—H2Cii	109.5	H4C—C4—H4Bii	45.9
N1—C3—H3A	109.5	H4Aii—C4—H4Bii	109.5
N1—C3—H3B	109.5	N1—C4—H4Cii	109.47 (18)
H3A—C3—H3B	109.5	H4A—C4—H4Cii	139.6
N1—C3—H3C	109.5	H4B—C4—H4Cii	45.9
H3A—C3—H3C	109.5	H4C—C4—H4Cii	66.5
H3B—C3—H3C	109.5	H4Aii—C4—H4Cii	109.5
N1—C3—H3Aii	109.5 (2)	H4Bii—C4—H4Cii	109.5
C4—N1—C1—O1	180.000 (1)	C4—N1—C1—C2	0.000 (1)
C3—N1—C1—O1	0.000 (1)	C3—N1—C1—C2	180.000 (1)

Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x, −y, z.

N,N-Dimethylacetamide–1-(dimethyl-λ⁴-azanylidene)ethan-1-ol dichloridoiodate (1/1) (III) . Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O1iii	0.64 (3)	1.79 (3)	2.4261 (11)	170 (4)
C2—H2A···Cl1iv	0.98	2.93	3.7461 (8)	141
C2—H2A···O1iii	0.98	2.61	3.3230 (9)	130
C2—H2C···Cl1	0.98	2.96	3.6902 (3)	132
C3—H3A···Cl1v	0.98	2.95	3.6479 (9)	129
C3—H3B···Cl1vi	0.98	2.89	3.7897 (8)	153
C3—H3C···O1vii	0.98	2.65	3.6256 (4)	176

Symmetry codes: (iii) −x+1, −y, −z+2; (iv) x−1/2, y−1/2, z; (v) −x+3/2, −y+1/2, −z+2; (vi) x+1/2, y−1/2, z; (vii) −x+3/2, −y−1/2, −z+2.

Funding Statement

GMZ thanks Baku State University for financial support. This publication was supported by the Russian Science Foundation (https://rscf.ru/project/22-73-00127/).