Crystal structure of N-(2,2,2-tri­chloro-1-hy­droxy­eth­yl)formamide

Mariyatra, M.B.; Stoeckli-Evans, H.

doi:10.1107/S2056989015020459

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Volume 71| Part 12| December 2015| Pages 1501-1504

https://doi.org/10.1107/S2056989015020459

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Crystal structure of N-(2,2,2-trichloro-1-hydroxyethyl)formamide

Mahimaidoss Baby Mariyatra ^a and Helen Stoeckli-Evans ^b ^*

^aDepartment of Chemistry, St. Xavier's College, Palayamkottai 627 002, India, and ^bInstitute of Physics, University of Neuchâtel, rue Emile-Argand 11, CH-2000 Neuchâtel, Switzerland
^*Correspondence e-mail: helen.stoeckli-evans@unine.ch, babymariyatra@gmail.com

Edited by P. C. Healy, Griffith University, Australia (Received 25 October 2015; accepted 28 October 2015; online 14 November 2015)

The title compound, C₃H₄Cl₃NO₂, crystallized with two independent molecules (A and B) in the asymmetric unit. The two molecules have the same conformation; the molecular overlap gives weighted and unit-weight r.m.s. fits of 0.047 and 0.043 Å, respectively. The conformation of the N-(hydroxethyl)formamide chains are very similar, as indicated by the C—N(H)—C=O and C—N(H)—C—O(H) torsion angles, which are, respectively, −1.8 (3) and −91.5 (2)° for molecule A, and −2.1 (3) and −95.7 (2)° for molecule B. In the crystal, individual molecules are linked by pairs of O—H⋯O hydrogen bonds, forming A–A and B–B inversion dimers with R₂²(12) ring motifs. The dimers are linked via N—H⋯O hydrogen bonds, forming alternating layers of A and B molecules parallel to the bc plane. Within the layers of B molecules, there are weak C—H⋯Cl hydrogen bonds present.

Keywords: crystal structure; trichlorohydroxyethyl; formamide; hydrogen bonding.

CCDC reference: 1009715

1. Chemical context

The skeletal structure of formamide is present in a number of medicinally important compounds. This has led to the use of formamides as key intermediates in numerous organic synthetic endeavours (Kobayashi et al., 1995 ; Chen et al., 2000 ; Jackson & Meth-Cohn, 1995 ). While formamides are useful formylating agents they have also found utility as easily accessible Lewis bases for promoting several organic transformations (Kobayashi & Nishio, 1994 ). Furthermore, in peptide synthesis the formyl group is a valued amino-protecting group (Martinez & Laur, 1982 ; Kraus, 1973 ). The title compound and related molecules have been found mentioned in several old patent literatures owing to their biocidal properties; both herbicidal (Schiewald et al., 1974 ) and fungicidal (Summers & Carter, 1977 ) action is known. The title compound is easily obtained by the reaction of 2,2,2-trichloroacetaldehyde and formamide (Sethi, 2006 ) and we describe herein its crystal structure.

2. Structural commentary

The title compound, Fig. 1, crystallized with two independent molecules (A and B) in the asymmetric unit. The arbitrarily chosen chirality of atoms C2 in molecule A and C5 in molecule B is the same. The backbones of the two molecules (O1/O3, C1/C4, C2/C5, N1/N2, C3/C6 and O2/O4) have almost identical conformations with weighted and unit-weight r.m.s. overlay fits of 0.047 and 0.043 Å, respectively, for the six atoms in each molecule (Fig. 2).

Figure 1
The molecular structure of the two independent molecules (A and B) of the title compound, showing the atom labelling. Displacement ellipsoids are drawn at the 50% probability level. The torsion angles C2—N1—C3—O2 and C3—N1—C2—O1 are −1.8 (3) and −91.5 (2)°, respectively, for molecule A, and C5—N2—C6—O4 and C6—N2—C5—O3 are −2.1 (3) and −95.7 (2)°, respectively, for molecule B.

Figure 2
A view of the molecular fit of the six backbone atoms (O1/O3, C1/C4, C2/C5, N1/N2, C3/C6 and O2/O4) of the A (black) and B (red) molecules of the title compound, calculated using the MolFit routine in PLATON (Spek, 2009

3. Supramolecular features

In the crystal, the individual molecules are linked by pairs of O—H⋯O hydrogen bonds, forming A–A and B–B inversion dimers with $[R_{2}^{2}]$ (12) ring motifs (Table 1 and Figs. 3 and 4). The dimers are linked via N—H⋯O hydrogen bonds, forming layers of A and B molecules parallel to the bc plane (Table 1 and Figs. 3 and 4). These latter hydrogen bonds lead to the formation of R₆⁴(20) ring motifs in each layer (Figs. 3 and 4). The layers stack alternately along the a axis, as shown in Fig. 5. Within the layers of B molecules there are weak C—H⋯Cl hydrogen bonds present (Table 1). There are no significant intermolecular interactions linking the layers.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1O⋯O2ⁱ	0.84 (3)	1.90 (4)	2.731 (2)	169 (3)
N1—H1N⋯O2ⁱⁱ	0.85 (2)	2.08 (3)	2.893 (2)	159 (2)
O3—H3O⋯O4ⁱⁱⁱ	0.76 (3)	1.97 (3)	2.721 (2)	174 (3)
N2—H2N⋯O4^iv	0.78 (3)	2.17 (3)	2.917 (2)	158 (2)
C6—H6⋯Cl4^v	1.00 (2)	2.91 (2)	3.586 (2)	125 (2)
Symmetry codes: (i) -x, -y+1, -z; (ii) $[-x, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (iii) -x+1, -y, -z+1; (iv) $[-x+1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (v) $[-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Figure 3
A view along the a axis of the hydrogen-bonded layer of A molecules of the title compound. Hydrogen bonds are shown as dashed lines (see Table 1

) and C-bound H atoms have been omitted for clarity.

Figure 4
A view along the a axis of the hydrogen-bonded layer of B molecules of the title compound. Hydrogen bonds are shown as dashed lines (see Table 1

) and C-bound H atoms have been omitted for clarity.

Figure 5
A view along the b axis of the crystal packing of the title compound, showing the alternating layers of hydrogen-bonded A (blue) and B (red) molecules. Hydrogen bonds are shown as dashed lines (see Table 1

) and C-bound H atoms have been omitted for clarity.

4. Database survey

A search of the Cambridge Structural Database (CSD, Version 5.36, last update May 2015; Groom & Allen, 2014 ) for the acyclic substructure C(=O)—N(H)—C(OH), viz. N-(hydroxmethyl)formamide, yielded 25 hits. The majority concern metal complexes of the ligand N-(hydroxymethyl)nicotinamide. Only one compound, N,N′-(1,2-dihydroxyethylene)diformamide (OGEJUG; Taheri & Moosavi, 2008 ) resembles the title compound. In the solid state, the whole molecule of this compound is generated by inversion symmetry. The geometric parameters are similar to those observed for the title compound, for example the conformation of the N-(hydroxmethyl)formamide chain as indicated by the C—N(H)—C—O(H) and C—N(H)—C=O torsion angles: 1.6 (2) and −99.09 (14)° for the above mentioned compound compared to −1.8 (3) and −91.5 (2)° for molecule A and −2.1 (3) and −95.7 (2)° for molecule B of the title compound (see Fig. 1).

5. Synthesis and crystallization

The title compound can be synthesized following a literature procedure (Sethi, 2006), by the reaction of 2,2,2-trichloroacetaldehyde and formamide. An old and discoloured sample of N-(2,2,2-trichloro-1-hydroxyethyl)formamide was dissolved in hot ethanol, followed by treatment with charcoal. The filtered solution was left to crystallize by slow evaporation, forming colourless block-like crystals (m.p. 393 K).

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. All of the H atoms were located from difference Fourier maps and freely refined.

Table 2
Experimental details

Crystal data
Chemical formula	C₃H₄Cl₃NO₂
M_r	192.42
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	173
a, b, c (Å)	13.7964 (8), 9.0798 (7), 12.2453 (7)
β (°)	114.413 (4)
V (Å³)	1396.80 (16)
Z	8
Radiation type	Mo Kα
μ (mm⁻¹)	1.24
Crystal size (mm)	0.45 × 0.43 × 0.40

Data collection
Diffractometer	Stoe IPDS 2
Absorption correction	Multi-scan (MULABS in PLATON; Spek, 2009 )
T_min, T_max	0.579, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	16347, 2645, 2468
R_int	0.056
(sin θ/λ)_max (Å⁻¹)	0.610

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.030, 0.078, 1.08
No. of reflections	2645
No. of parameters	196
H-atom treatment	All H-atom parameters refined
Δρ_max, Δρ_min (e Å⁻³)	0.82, −0.55
Computer programs: X-AREA and X-RED32 (Stoe & Cie, 2009 ), SHELXS2014 (Sheldrick, 2008 ), SHELXL2014 (Sheldrick, 2015 ), PLATON (Spek, 2009) and Mercury (Macrae et al., 2008 ).

Supporting information

CCDC reference: 1009715

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2056989015020459/hg5462sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989015020459/hg5462Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2056989015020459/hg5462Isup3.cml

checkCIF report

Computing details top

Data collection: X-AREA (Stoe & Cie, 2009); cell refinement: X-AREA (Stoe & Cie, 2009); data reduction: X-RED32 (Stoe & Cie, 2009); program(s) used to solve structure: SHELXS2014 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: PLATON (Spek, 2009) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL2014 (Sheldrick, 2015) and PLATON (Spek, 2009).

N-(2,2,2-Trichloro-1-hydroxyethyl)formamide top

Crystal data top

C₃H₄Cl₃NO₂	F(000) = 768
M_r = 192.42	D_x = 1.830 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 13.7964 (8) Å	Cell parameters from 22309 reflections
b = 9.0798 (7) Å	θ = 1.6–26.2°
c = 12.2453 (7) Å	µ = 1.24 mm⁻¹
β = 114.413 (4)°	T = 173 K
V = 1396.80 (16) Å³	Block, colourless
Z = 8	0.45 × 0.43 × 0.40 mm

Data collection top

Stoe IPDS 2 diffractometer	2645 independent reflections
Radiation source: fine-focus sealed tube	2468 reflections with I > 2σ(I)
Plane graphite monochromator	R_int = 0.056
φ + ω scans	θ_max = 25.7°, θ_min = 1.6°
Absorption correction: multi-scan (MULABS in PLATON; Spek, 2009)	h = −15→16
T_min = 0.579, T_max = 1.000	k = −11→11
16347 measured reflections	l = −14→14

Refinement top

Refinement on F²	Hydrogen site location: difference Fourier map
Least-squares matrix: full	All H-atom parameters refined
R[F² > 2σ(F²)] = 0.030	w = 1/[σ²(F_o²) + (0.0333P)² + 1.2964P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.078	(Δ/σ)_max < 0.001
S = 1.08	Δρ_max = 0.82 e Å⁻³
2645 reflections	Δρ_min = −0.55 e Å⁻³
196 parameters	Extinction correction: SHELXL2014 (Sheldrick, 2015), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.0089 (9)

Special details top

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

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Cl1	0.13449 (5)	0.04880 (6)	0.08600 (5)	0.03428 (17)
Cl2	0.22308 (4)	0.28605 (6)	−0.00018 (5)	0.03123 (16)
Cl3	0.28102 (5)	0.25302 (8)	0.25345 (5)	0.04298 (19)
O1	−0.00275 (12)	0.31695 (18)	−0.01499 (14)	0.0284 (4)
H1O	0.005 (3)	0.366 (4)	−0.069 (3)	0.058 (10)*
O2	0.00144 (13)	0.53996 (16)	0.21058 (14)	0.0295 (4)
N1	0.04737 (14)	0.30393 (19)	0.18967 (16)	0.0213 (4)
H1N	0.0392 (18)	0.215 (3)	0.207 (2)	0.020 (6)*
C1	0.17653 (17)	0.2341 (2)	0.10963 (19)	0.0234 (4)
C2	0.08245 (16)	0.3364 (2)	0.09670 (18)	0.0217 (4)
H2	0.1107 (18)	0.434 (3)	0.1068 (19)	0.020 (6)*
C3	0.00885 (17)	0.4079 (2)	0.23751 (18)	0.0237 (4)
H3	−0.0156 (18)	0.374 (3)	0.299 (2)	0.026 (6)*
Cl4	0.64204 (5)	0.45558 (5)	0.52480 (5)	0.03177 (16)
Cl5	0.78172 (4)	0.22393 (6)	0.51229 (5)	0.02994 (15)
Cl6	0.71719 (4)	0.23240 (7)	0.70803 (5)	0.03280 (16)
O3	0.49315 (12)	0.20023 (18)	0.51142 (15)	0.0274 (3)
H3O	0.497 (2)	0.153 (3)	0.564 (3)	0.036 (8)*
O4	0.50422 (13)	−0.04575 (15)	0.29695 (13)	0.0281 (3)
N2	0.54593 (14)	0.19299 (19)	0.35510 (15)	0.0208 (4)
H2N	0.5415 (19)	0.274 (3)	0.332 (2)	0.023 (6)*
C4	0.67565 (16)	0.2671 (2)	0.55274 (18)	0.0216 (4)
C5	0.57819 (16)	0.1686 (2)	0.48142 (18)	0.0206 (4)
H5	0.6025 (16)	0.066 (2)	0.5015 (18)	0.012 (5)*
C6	0.51071 (16)	0.0854 (2)	0.27421 (18)	0.0230 (4)
H6	0.4911 (19)	0.119 (3)	0.190 (2)	0.028 (6)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0493 (4)	0.0157 (3)	0.0449 (3)	0.0062 (2)	0.0265 (3)	0.0024 (2)
Cl2	0.0363 (3)	0.0317 (3)	0.0356 (3)	0.0029 (2)	0.0248 (2)	0.0016 (2)
Cl3	0.0250 (3)	0.0729 (5)	0.0282 (3)	0.0012 (3)	0.0081 (2)	−0.0095 (3)
O1	0.0292 (8)	0.0315 (9)	0.0259 (8)	0.0064 (6)	0.0127 (7)	0.0100 (7)
O2	0.0478 (10)	0.0170 (7)	0.0307 (8)	0.0078 (6)	0.0232 (7)	0.0031 (6)
N1	0.0268 (9)	0.0138 (8)	0.0279 (9)	0.0012 (7)	0.0159 (7)	0.0025 (7)
C1	0.0259 (10)	0.0227 (10)	0.0236 (10)	0.0014 (8)	0.0121 (9)	−0.0014 (8)
C2	0.0272 (10)	0.0144 (10)	0.0275 (10)	0.0016 (8)	0.0154 (8)	0.0010 (8)
C3	0.0288 (11)	0.0221 (10)	0.0229 (10)	0.0034 (8)	0.0133 (9)	0.0013 (8)
Cl4	0.0415 (3)	0.0152 (2)	0.0346 (3)	−0.0028 (2)	0.0117 (2)	−0.0021 (2)
Cl5	0.0247 (3)	0.0366 (3)	0.0304 (3)	0.0009 (2)	0.0133 (2)	0.0020 (2)
Cl6	0.0336 (3)	0.0425 (3)	0.0191 (3)	−0.0029 (2)	0.0077 (2)	0.0028 (2)
O3	0.0287 (8)	0.0303 (8)	0.0265 (8)	−0.0020 (6)	0.0150 (7)	0.0051 (7)
O4	0.0426 (9)	0.0170 (7)	0.0273 (8)	−0.0055 (6)	0.0171 (7)	−0.0019 (6)
N2	0.0271 (9)	0.0132 (8)	0.0202 (9)	−0.0017 (7)	0.0080 (7)	0.0025 (7)
C4	0.0253 (10)	0.0199 (10)	0.0199 (10)	−0.0008 (8)	0.0096 (8)	0.0008 (7)
C5	0.0253 (10)	0.0147 (10)	0.0216 (10)	−0.0018 (8)	0.0095 (8)	0.0016 (7)
C6	0.0270 (10)	0.0211 (10)	0.0217 (10)	−0.0021 (8)	0.0111 (8)	−0.0007 (8)

Geometric parameters (Å, º) top

Cl1—C1	1.764 (2)	Cl4—C4	1.769 (2)
Cl2—C1	1.777 (2)	Cl5—C4	1.772 (2)
Cl3—C1	1.764 (2)	Cl6—C4	1.773 (2)
O1—C2	1.398 (3)	O3—C5	1.396 (3)
O1—H1O	0.84 (3)	O3—H3O	0.76 (3)
O2—C3	1.236 (3)	O4—C6	1.235 (3)
N1—C3	1.332 (3)	N2—C6	1.332 (3)
N1—C2	1.440 (3)	N2—C5	1.439 (3)
N1—H1N	0.85 (2)	N2—H2N	0.78 (3)
C1—C2	1.550 (3)	C4—C5	1.549 (3)
C2—H2	0.96 (2)	C5—H5	0.99 (2)
C3—H3	0.99 (2)	C6—H6	1.00 (2)

C2—O1—H1O	112 (2)	C5—O3—H3O	110 (2)
C3—N1—C2	121.88 (17)	C6—N2—C5	122.84 (17)
C3—N1—H1N	116.3 (16)	C6—N2—H2N	118.0 (18)
C2—N1—H1N	120.8 (16)	C5—N2—H2N	118.7 (18)
C2—C1—Cl3	110.37 (14)	C5—C4—Cl4	110.64 (14)
C2—C1—Cl1	110.49 (14)	C5—C4—Cl5	109.84 (14)
Cl3—C1—Cl1	109.52 (11)	Cl4—C4—Cl5	109.91 (11)
C2—C1—Cl2	108.24 (14)	C5—C4—Cl6	108.82 (14)
Cl3—C1—Cl2	109.15 (11)	Cl4—C4—Cl6	108.79 (11)
Cl1—C1—Cl2	109.04 (11)	Cl5—C4—Cl6	108.80 (11)
O1—C2—N1	109.04 (17)	O3—C5—N2	109.32 (16)
O1—C2—C1	110.74 (16)	O3—C5—C4	111.15 (16)
N1—C2—C1	109.73 (16)	N2—C5—C4	109.14 (16)
O1—C2—H2	112.1 (13)	O3—C5—H5	111.4 (12)
N1—C2—H2	109.8 (14)	N2—C5—H5	109.6 (12)
C1—C2—H2	105.3 (14)	C4—C5—H5	106.2 (12)
O2—C3—N1	125.03 (19)	O4—C6—N2	125.30 (19)
O2—C3—H3	119.1 (14)	O4—C6—H6	120.9 (14)
N1—C3—H3	115.9 (14)	N2—C6—H6	113.7 (14)

C3—N1—C2—O1	−91.5 (2)	C6—N2—C5—O3	−95.7 (2)
C3—N1—C2—C1	147.08 (19)	C6—N2—C5—C4	142.52 (19)
Cl3—C1—C2—O1	−177.16 (14)	Cl4—C4—C5—O3	−58.44 (19)
Cl1—C1—C2—O1	−55.9 (2)	Cl5—C4—C5—O3	−179.96 (13)
Cl2—C1—C2—O1	63.45 (19)	Cl6—C4—C5—O3	61.03 (19)
Cl3—C1—C2—N1	−56.7 (2)	Cl4—C4—C5—N2	62.20 (19)
Cl1—C1—C2—N1	64.54 (19)	Cl5—C4—C5—N2	−59.31 (19)
Cl2—C1—C2—N1	−176.13 (14)	Cl6—C4—C5—N2	−178.33 (14)
C2—N1—C3—O2	−1.8 (3)	C5—N2—C6—O4	−2.1 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1O···O2ⁱ	0.84 (3)	1.90 (4)	2.731 (2)	169 (3)
N1—H1N···O2ⁱⁱ	0.85 (2)	2.08 (3)	2.893 (2)	159 (2)
O3—H3O···O4ⁱⁱⁱ	0.76 (3)	1.97 (3)	2.721 (2)	174 (3)
N2—H2N···O4^iv	0.78 (3)	2.17 (3)	2.917 (2)	158 (2)
C6—H6···Cl4^v	1.00 (2)	2.91 (2)	3.586 (2)	125 (2)

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

Acknowledgements

MBM thanks the Department of Chemistry, St Xavier's College, for support of this work. HSE thanks the XRD Laboratory, CSEM, Neuchâtel, for access to the X-ray diffractometer.

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Volume 71| Part 12| December 2015| Pages 1501-1504

https://doi.org/10.1107/S2056989015020459

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