Polar crystal of vanillylformamide through replacement of the alkene by an isosteric formamide group

Baillargeon, P.; Rahem, T.; Amigo, C.; Fortin, D.; Dory, Y.L.

doi:10.1107/S2414314618016309

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 3| Part 12| December 2018| x181630

https://doi.org/10.1107/S2414314618016309

Open

access

Polar crystal of vanillylformamide through replacement of the alkene by an isosteric formamide group

Pierre Baillargeon,^a ^* Tarik Rahem,^a Carl Amigo,^a Daniel Fortin ^b and Yves L. Dory ^c

^aDépartement de Chimie, Cégep de Sherbrooke, 475 Rue du Cégep, Sherbrooke, Québec, J1E 4K1, Canada, ^bLaboratoire d'Analyses Structurales par Diffraction des rayons-X, Département de Chimie, Université de Sherbrooke, 2500, Boulevard de l'Université, Sherbrooke, Québec, J1K 2R1, Canada, and ^cLaboratoire de Synthèse Supramoléculaire, Département de Chimie, Institut de Pharmacologie, Université de Sherbrooke, 3001 12e Avenue Nord, Sherbrooke, Québec, J1H 5N4, Canada
^*Correspondence e-mail: Pierre.Baillargeon@usherbrooke.ca

Edited by L. Fabian, University of East Anglia, England (Received 27 September 2018; accepted 16 November 2018; online 5 December 2018)

Vanillylformamide [systematic name: N-(4-hydroxy-3-methoxybenzyl)formamide], C₉H₁₁NO₃, (II), has been synthesized from vanillylamine hydrochloride and studied by single-crystal X-ray diffraction. Compound (II) and the well known biologically active eugenol compound (I) can be considered to be `isosteres' of each other, since they share comparable molecular shape and volume. The product (II) crystallizes in the space group P1. In the crystal, the vanillylformamide molecules are linked mainly by N—H⋯O, O—H⋯O and Csp²—H⋯O hydrogen bonds, forming infinite two-dimensional polar sheets. These two-dimensional layers pack in a parallel fashion, constructing a polar three-dimensional network. Except for van der Waals forces and weak Csp³—H⋯O hydrogen bonds, there are no significant intermolecular interactions between the layers. A Cambridge Structural Database search revealed that vanillylamide-related crystals are scarce.

Keywords: polar crystal structure; vanillylamine; eugenol; capsaicin analogs; isosteres.

CCDC reference: 1846884

Structure description

Eugenol is a natural molecule that exhibits versatile properties useful in various domains. Indeed, there is increasing interest from the scientific and industrial community in eugenol-based polymers (Miao et al. 2017 ; Guzmán et al., 2017 ; Chen et al., 2017 ; Modjinou et al., 2016 ; Wan et al., 2016a ,b ; Deng et al., 2015 ). Moreover, this bioactive compound has high potential as a therapeutic agent since it has antiparasitic, antiviral, antibacterial, antifungal, anticancer, antioxidant and anti-inflammatory activities (Raja et al., 2015 ; Khalil et al., 2017 ). On the other hand, to the best of our knowledge, no study on the bioisosteres of eugenol has been undertaken. The definition of bioisosterism has been broadened by Burger (1991 ) as `Compounds or groups that possess near-equal molecular shapes and volumes, approximately the same distribution of electrons, and which exhibit similar physical properties'. Thus, chemical modification of lead compounds represents a rational approach in drug design (Patani et al., 1996 ). Alkenes and amides are isosteric since they are both planar and possess two sp²-hybridized atoms in the main chain (Choudhary et al., 2011 ). In this context, effort has been focused in our group to determine the crystal structure of the vanillylformamide (II), which mimics eugenol (I) (Fig. 1) and could have some biological interest. We were also pleased that the title compound crystallized in a polar space group, since several functional properties of advanced materials (piezoelectricity, pyroelectricity, ferroelectricity, second harmonic generation, and electro-optic response) are only allowed or significantly enhanced in polar crystal structures (Centore et al., 2012 , 2016 ; Takahashi et al., 2016 ).

Figure 1
Eugenol (I) and the title compound (II).

The molecular structure of the title compound (II) is shown in Fig. 2. All bond lengths and angles are within normal ranges. Although the O3—H3⋯O1 angle [113 (5)°] is far from linear, we can consider that the phenol and methoxy group are partners in an intramolecular hydrogen bond (Hunt et al., 2005 ). The cis/trans conformational equilibrium of the formamide group is fixed in the solid state in the trans conformation, as can be confirmed by the torsion angle C5—N1—C6—O2 [1.3 (6)°].

Figure 2
The molecular structure of compound (II), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are shown as fixed-size spheres of 0.30 Å.

In the crystal, the vanillylformamide molecules are linked by a series of classical hydrogen bonds (N1—H1⋯O2, O3—H3⋯O1, O3—H3⋯O2; Table 1) and non-conventional Csp²—H⋯O hydrogen bonds (C6—H6⋯O3; Table 1), forming infinite two-dimensional polar sheets [Fig. 3(a)] parallel to (01 $[\overline{1}]$ ). Moreover, C6⋯O1 close contacts stabilize this architecture. The stacking pattern reveals that each layer is oriented in the same direction [Fig. 3(b)], generating a complete three-dimensional polar network. The main intermolecular contacts between layers [Fig. 2(c)] consist of van der Waals forces (C1⋯H7 and H1B⋯H7) and weak Csp³—H⋯O hydrogen bonds (C5—H5B⋯O3 and C5—H5A⋯O3 of neighbouring molecules).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯O2ⁱ	0.88	2.05	2.910 (4)	167
O3—H3⋯O1	0.96 (3)	2.15 (7)	2.672 (4)	113 (5)
C6—H6⋯O3ⁱⁱ	0.95	2.54	3.391 (5)	149
O3—H3⋯O2ⁱⁱⁱ	0.96 (3)	1.90 (4)	2.771 (4)	149 (6)
C5—H5B⋯O3^iv	0.99	2.60	3.374 (5)	135
C5—H5A⋯O3^v	0.99	2.70	3.676 (5)	167
Symmetry codes: (i) x-1, y, z; (ii) x-1, y-1, z-1; (iii) x, y+1, z+1; (iv) x, y, z-1; (v) x-1, y, z-1.

Figure 3
(a) Main hydrogen bonds and dipole–dipole interactions inside the polar sheets of vanillylformamide (II). (b) Stacking of the polar sheets along the a axis. (c) Weak interactions between the polar sheets.

A search of the Cambridge Structural Database (CSD, Version 5.38, update May 2017; Groom et al., 2016 ) indicated that 11 vanillylamide derivatives have been reported [FABVAF and FABVEJ (Oliver et al., 1985 ); FABVAF01 (David et al., 1998 ); FOSXOB (Winkler et al., 2009 ); FOWTUH (Xia et al., 2009 ); FOWTUH01 and KUTMAO01 (Wang et al., 2010 ); KUTMAO (Huang et al., 2010 ); QUZKOM (Xia et al., 2010 ); SOFTEN (Zhang et al., 2008 ); SOFTEN01 (Zhang & Cai, 2008 )]. However, there was no structural report on vanillylamide analogues containing small amide units (such as a formamide) that could be considered as true isosteres of eugenol.

Synthesis and crystallization

Vanillylformamide (II) was already characterized in the literature through NMR spectroscopy (Baldessari et al., 1987 ). However, this molecule has no known crystal structure.

Compound (II): To a solution of 4-nitrophenylformate (575 mg, 3.44 mmol) in ethyl acetate (10 ml) at room temperature was added potassium carbonate (715 mg, 5.17 mmol) and vanillylamine hydrochloride (717 mg, 3.78 mmol) under an argon atmosphere. After 1 h of stirring at room temperature, a catalytic amount of water (30 µl) was added, the resulting mixture was stirred for an additional 3 h. The reaction was followed by TLC (30/70 acetone/DCM). The reaction mixture was poured in HCl 0.1M (15 ml) and then extracted twice with ethyl acetate (2 × 15 ml). Hexane (50 ml) was added to the combined organic layers and the resulting organic phase was then filtrated directly through a silica gel pad, eluting with 100 ml of acetone/DCM (5:95) and 100 ml of acetone/DCM (30:70), to yield compound (II) as a yellowish white crystalline powder (485 mg, 78%). Single crystals suitable for X-ray diffraction were prepared by slow evaporation of an ether/acetone/hexane (70:5:25) solution of (II) at room temperature.

R_f = 0.37 (acetone/DCM 30:70); ¹H NMR (400 MHz, CDCl₃, p.p.m.): 8.20 (s, 1H), 6.86–6.71 (m, 3H), 6.03 (m, 1H), 5.86 (s, 1H), 4.37 (d, J = 5.84 Hz, 2H), 3.85 (s, 3H).

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. The absolute structure could not be determined reliably from the collected diffraction data.

Table 2
Experimental details

Crystal data
Chemical formula	C₉H₁₁NO₃
M_r	181.19
Crystal system, space group	Triclinic, P1
Temperature (K)	173
a, b, c (Å)	4.8011 (2), 6.5522 (3), 7.5052 (3)
α, β, γ (°)	93.618 (2), 107.044 (2), 95.658 (2)
V (Å³)	223.58 (2)
Z	1
Radiation type	Cu Kα
μ (mm⁻¹)	0.85
Crystal size (mm)	0.32 × 0.16 × 0.12

Data collection
Diffractometer	Bruker APEXII
Absorption correction	Multi-scan (SADABS; Bruker, 2012 )
T_min, T_max	0.574, 0.753
No. of measured, independent and observed [I > 2σ(I)] reflections	2726, 1206, 1139
R_int	0.051
(sin θ/λ)_max (Å⁻¹)	0.609

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.052, 0.154, 1.12
No. of reflections	1206
No. of parameters	123
No. of restraints	4
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.25, −0.23
Computer programs: APEX2 (Bruker, 2012), SAINT (Bruker, 2012), SORTAV (Blessing, 1995 ), SHELXS (Sheldrick, 2008 ), SHELXL2016/6 (Sheldrick, 2015 ), ORTEP for Windows (Farrugia, 2012 ) and Mercury (Macrae et al., 2008 ), WinGX (Farrugia, 2012) and publCIF (Westrip, 2010 ).

Structural data

CCDC reference: 1846884

Crystal structure: contains datablocks global, II. DOI: https://doi.org/10.1107/S2414314618016309/fy2132sup1.cif

Structure factors: contains datablock II. DOI: https://doi.org/10.1107/S2414314618016309/fy2132IIsup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314618016309/fy2132Isup3.smi

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2012); cell refinement: SAINT (Bruker, 2012); data reduction: SORTAV (Blessing, 1995); program(s) used to solve structure: SHELXS (Sheldrick, 2008); program(s) used to refine structure: SHELXL2016/6 (Sheldrick, 2015); molecular graphics: ORTEP for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2008); software used to prepare material for publication: WinGX (Farrugia, 2012) and publCIF (Westrip, 2010).

(II) top

Crystal data top

C₉H₁₁NO₃	Z = 1
M_r = 181.19	F(000) = 96
Triclinic, P1	D_x = 1.346 Mg m⁻³
Hall symbol: P 1	Cu Kα radiation, λ = 1.54178 Å
a = 4.8011 (2) Å	Cell parameters from 2759 reflections
b = 6.5522 (3) Å	θ = 6.2–70.7°
c = 7.5052 (3) Å	µ = 0.85 mm⁻¹
α = 93.618 (2)°	T = 173 K
β = 107.044 (2)°	Prism, colorless
γ = 95.658 (2)°	0.32 × 0.16 × 0.12 mm
V = 223.58 (2) Å³

Data collection top

Bruker APEXII diffractometer	1206 independent reflections
Radiation source: sealed x-ray tube	1139 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.051
φ or ω oscillation scans	θ_max = 69.8°, θ_min = 6.2°
Absorption correction: multi-scan (SADABS; Bruker, 2012)	h = −5→5
T_min = 0.574, T_max = 0.753	k = −7→7
2726 measured reflections	l = −9→8

Refinement top

Refinement on F²	0 constraints
Least-squares matrix: full	Hydrogen site location: mixed
R[F² > 2σ(F²)] = 0.052	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.154	w = 1/[σ²(F_o²) + (0.0912P)² + 0.0525P] where P = (F_o² + 2F_c²)/3
S = 1.12	(Δ/σ)_max < 0.001
1206 reflections	Δρ_max = 0.25 e Å⁻³
123 parameters	Δρ_min = −0.23 e Å⁻³
4 restraints

Special details top

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.

Refinement. Hydrogen atoms bound to carbon atoms were positioned with idealized geometry and refined isotropically using a riding model, with U_iso(H) = 1.2 U_eq(C) and C—H = 0.95 Å for aromatic, U_iso(H) = 1.2 U_eq(C) and C—H = 0.99 Å for methylene and U_iso(H) = 1.5 U_eq(C) and C—H = 0.98 Å for methyl groups. The N-bound H atom was placed in idealized position with N—H = 0.88 Å and refined in riding mode with U_iso(H) = 1.2 U_eq(N). The hydroxyl H atom was refined independently in isotropic mode, with an O—H distance restraint of 0.96 (2) Å.

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

	x	y	z	U_iso*/U_eq
O1	0.7872 (8)	0.7526 (5)	0.5754 (4)	0.0436 (9)
O2	1.0943 (7)	−0.0646 (5)	−0.0270 (5)	0.0376 (8)
O3	1.2189 (6)	0.5811 (5)	0.8054 (4)	0.0346 (8)
N1	0.6936 (8)	0.0863 (6)	−0.0091 (5)	0.0313 (8)
H1	0.506646	0.0619	−0.016887	0.038*
C1	0.5812 (13)	0.8622 (8)	0.4558 (8)	0.0457 (12)
H1A	0.673811	0.934512	0.373509	0.069*
H1B	0.513623	0.962513	0.531259	0.069*
H1C	0.413277	0.765528	0.379819	0.069*
C2	0.8948 (9)	0.6005 (6)	0.4953 (6)	0.0300 (10)
C3	0.8016 (9)	0.5279 (6)	0.3069 (6)	0.0313 (9)
H3A	0.648153	0.586589	0.222842	0.038*
C4	0.9284 (9)	0.3719 (6)	0.2397 (6)	0.0296 (9)
C5	0.8312 (9)	0.2985 (7)	0.0327 (6)	0.0330 (10)
H5A	0.690774	0.388824	−0.035372	0.04*
H5B	1.004057	0.312362	−0.014027	0.04*
C6	0.8314 (9)	−0.0728 (6)	−0.0364 (6)	0.0318 (9)
H6	0.718873	−0.204814	−0.065598	0.038*
C7	1.1468 (11)	0.2848 (7)	0.3628 (6)	0.0387 (11)
H7	1.235762	0.177733	0.317846	0.046*
C8	1.2385 (10)	0.3531 (6)	0.5538 (6)	0.0382 (11)
H8	1.385838	0.289743	0.638179	0.046*
C9	1.1167 (9)	0.5113 (6)	0.6200 (5)	0.0295 (10)
H3	1.144 (16)	0.711 (7)	0.817 (10)	0.061 (18)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.054 (2)	0.0452 (19)	0.0316 (18)	0.0282 (16)	0.0062 (14)	−0.0004 (14)
O2	0.0287 (17)	0.0393 (17)	0.0418 (19)	0.0016 (12)	0.0094 (13)	−0.0082 (14)
O3	0.0383 (17)	0.0347 (16)	0.0260 (15)	0.0064 (12)	0.0027 (12)	−0.0021 (12)
N1	0.0234 (16)	0.0360 (18)	0.0309 (19)	0.0017 (13)	0.0047 (14)	−0.0041 (14)
C1	0.054 (3)	0.047 (3)	0.038 (3)	0.024 (2)	0.011 (2)	0.009 (2)
C2	0.033 (2)	0.027 (2)	0.030 (2)	0.0017 (17)	0.0105 (19)	0.0021 (17)
C3	0.032 (2)	0.032 (2)	0.026 (2)	0.0069 (17)	0.0025 (17)	0.0053 (16)
C4	0.028 (2)	0.030 (2)	0.029 (2)	0.0017 (16)	0.0052 (17)	0.0032 (17)
C5	0.038 (2)	0.035 (2)	0.024 (2)	0.0041 (17)	0.0066 (18)	0.0056 (16)
C6	0.035 (2)	0.033 (2)	0.025 (2)	−0.0045 (17)	0.0096 (17)	−0.0031 (16)
C7	0.047 (3)	0.037 (2)	0.028 (2)	0.015 (2)	0.0018 (19)	−0.0023 (18)
C8	0.040 (3)	0.036 (3)	0.032 (3)	0.014 (2)	−0.002 (2)	0.0008 (19)
C9	0.031 (2)	0.029 (2)	0.025 (2)	−0.0005 (17)	0.0059 (18)	−0.0017 (17)

Geometric parameters (Å, º) top

O1—C2	1.352 (6)	C2—C9	1.400 (6)
O1—C1	1.415 (6)	C3—C4	1.382 (6)
O2—C6	1.239 (5)	C3—H3A	0.95
O3—C9	1.364 (5)	C4—C7	1.376 (6)
O3—H3	0.96 (3)	C4—C5	1.516 (6)
N1—C6	1.325 (6)	C5—H5A	0.99
N1—C5	1.453 (6)	C5—H5B	0.99
N1—H1	0.88	C6—H6	0.95
C1—H1A	0.98	C7—C8	1.400 (6)
C1—H1B	0.98	C7—H7	0.95
C1—H1C	0.98	C8—C9	1.374 (6)
C2—C3	1.389 (6)	C8—H8	0.95

C2—O1—C1	117.7 (3)	C3—C4—C5	120.6 (4)
C9—O3—H3	106 (4)	N1—C5—C4	113.5 (3)
C6—N1—C5	124.2 (3)	N1—C5—H5A	108.9
C6—N1—H1	117.9	C4—C5—H5A	108.9
C5—N1—H1	117.9	N1—C5—H5B	108.9
O1—C1—H1A	109.5	C4—C5—H5B	108.9
O1—C1—H1B	109.5	H5A—C5—H5B	107.7
H1A—C1—H1B	109.5	O2—C6—N1	125.7 (4)
O1—C1—H1C	109.5	O2—C6—H6	117.1
H1A—C1—H1C	109.5	N1—C6—H6	117.1
H1B—C1—H1C	109.5	C4—C7—C8	120.4 (4)
O1—C2—C3	125.9 (4)	C4—C7—H7	119.8
O1—C2—C9	114.6 (4)	C8—C7—H7	119.8
C3—C2—C9	119.5 (4)	C9—C8—C7	120.4 (4)
C4—C3—C2	121.1 (4)	C9—C8—H8	119.8
C4—C3—H3A	119.5	C7—C8—H8	119.8
C2—C3—H3A	119.5	O3—C9—C8	119.3 (4)
C7—C4—C3	119.2 (4)	O3—C9—C2	121.3 (4)
C7—C4—C5	120.3 (4)	C8—C9—C2	119.4 (4)

C1—O1—C2—C3	−6.5 (6)	C3—C4—C7—C8	0.2 (7)
C1—O1—C2—C9	174.5 (4)	C5—C4—C7—C8	179.6 (4)
O1—C2—C3—C4	179.7 (4)	C4—C7—C8—C9	−1.6 (7)
C9—C2—C3—C4	−1.3 (6)	C7—C8—C9—O3	−177.1 (4)
C2—C3—C4—C7	1.2 (6)	C7—C8—C9—C2	1.5 (7)
C2—C3—C4—C5	−178.1 (3)	O1—C2—C9—O3	−2.3 (5)
C6—N1—C5—C4	−97.8 (5)	C3—C2—C9—O3	178.5 (4)
C7—C4—C5—N1	65.2 (5)	O1—C2—C9—C8	179.0 (4)
C3—C4—C5—N1	−115.5 (4)	C3—C2—C9—C8	−0.1 (6)
C5—N1—C6—O2	1.3 (6)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O2ⁱ	0.88	2.05	2.910 (4)	167
O3—H3···O1	0.96 (3)	2.15 (7)	2.672 (4)	113 (5)
C6—H6···O3ⁱⁱ	0.95	2.54	3.391 (5)	149
O3—H3···O2ⁱⁱⁱ	0.96 (3)	1.90 (4)	2.771 (4)	149 (6)
C5—H5B···O3^iv	0.99	2.60	3.374 (5)	135
C5—H5A···O3^v	0.99	2.70	3.676 (5)	167

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

Funding information

Funding for this research was provided by: Fonds de Recherche du Québec - Nature et Technologies (grant No. 2016-CO-194882; grant No. 2019-CO-254502).

References

Baldessari, A. & Gros, E. G. (1987). Magn. Reson. Chem. 25, 1012–1018. CrossRef Google Scholar
Blessing, R. H. (1995). Acta Cryst. A51, 33–38. CrossRef CAS Web of Science IUCr Journals Google Scholar
Bruker (2012). APEX2, SAINT and SADABS. Bruker AXS Inc, Madison, Wisconsin, USA. Google Scholar
Burger, A. (1991). Prog. Drug Res. 37, 287–371. PubMed CAS Google Scholar
Centore, R., Fusco, S., Capone, F. & Causà, M. (2016). Cryst. Growth Des. 16, 2260–2265. CrossRef Google Scholar
Centore, R., Jazbinsek, M., Tuzi, A., Roviello, A., Capobianco, A. & Peluso, A. (2012). CrystEngComm, 14, 2645–2653. Web of Science CrossRef CAS Google Scholar
Chen, G., Feng, J., Qiu, W. & Zhao, Y. (2017). RSC Adv. 7, 55967–55976. CrossRef Google Scholar
Choudhary, A. & Raines, R. T. (2011). ChemBioChem, 12, 1801–1807. CrossRef Google Scholar
David, W. I. F., Shankland, K. & Shankland, N. (1998). Chem. Commun. pp. 931–932. Web of Science CrossRef Google Scholar
Deng, J., Yang, B., Chen, C. & Liang, J. (2015). ACS Sustainable Chem. Eng. 3, 599-605. CrossRef Google Scholar
Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849–854. Web of Science CrossRef CAS IUCr Journals Google Scholar
Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171–179. Web of Science CrossRef IUCr Journals Google Scholar
Guzmán, D., Ramis, X., Fernández-Francos, X., De la Flor, S. & Serra, A. (2017). Eur. Polym. J. 93, 530–544. Google Scholar
Huang, Y.-L., Wang, W.-L. & Shan, S. (2010). Acta Cryst. E66, o877. Web of Science CrossRef IUCr Journals Google Scholar
Hunt, N. T., Turner, A. R. & Wynne, K. (2005). J. Phys. Chem. B, 109, 19008–19017. CrossRef Google Scholar
Khalil, A. A., Rahman, U. U., Khan, M. R., Sahar, A., Mehmood, T. & Khan, M. (2017). RSC Adv. 7, 32669–32681. CrossRef Google Scholar
Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466–470. Web of Science CrossRef CAS IUCr Journals Google Scholar
Miao, J.-T., Yuan, L., Guan, Q., Liang, G. & Gu, A. (2017). ACS Sustainable Chem. Eng. 5, 7003–7011. CrossRef Google Scholar
Modjinou, T., Versace, D.-L., Abbad-Andallousi, S., Bousserrhine, N., Dubot, P., Langlois, V. & Renard, E. (2016). React. Funct. Polym. 101, 47–53. CrossRef Google Scholar
Oliver, J. D. (1985). ACA Abstr. Papers (Winter) 13, 57. Google Scholar
Patani, G. A. & LaVoie, E. J. (1996). Chem. Rev. 96, 3147–3176. CrossRef PubMed CAS Web of Science Google Scholar
Raja, M. R. C., Srinivasan, V., Selvaraj, S. & Mahapatra, S. K. (2015). Pharm. Anal. Acta 6, 367. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Sheldrick, G. M. (2015). Acta Cryst. C71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Takahashi, K., Hoshino, N., Takeda, T., Satomi, K., Suzuki, Y., Noro, S.-I., Nakamura, T., Kawamata, J. & Akutagawa, T. (2016). Dalton Trans. 45, 3398–3406. CrossRef Google Scholar
Wan, J., Gan, B., Li, C., Molina-Aldareguia, J., Kalali, E. N., Wang, X. & Wang, D.-Y. (2016a). Chem. Eng. J. 284, 1080–1093. CrossRef Google Scholar
Wan, J., Zhao, J., Gan, B., Li, C., Molina-Aldareguia, J., Zhao, Y., Pan, Y.-T. & Wang, D.-Y. (2016b). ACS Sustainable Chem. Eng. 4, 2869-2880. CrossRef Google Scholar
Wang, W.-L., Huang, Y.-L., Hu, W.-X. & Shan, S. (2010). Gaodeng Xuexiao Huaxue Xuebao (Chem. J. Chin. Univ.) 31, 2400-2406. Google Scholar
Westrip, S. P. (2010). J. Appl. Cryst. 43, 920–925. Web of Science CrossRef CAS IUCr Journals Google Scholar
Winkler, M., Moraux, T., Khairy, H. A., Scott, R. H., Slawin, A. M. & O'Hagan, D. (2009). ChemBioChem, 10, 823–828. CrossRef Google Scholar
Xia, L.-Y., Wang, W.-L., Huang, Y.-L. & Shan, S. (2010). Acta Cryst. E66, o1700. CrossRef IUCr Journals Google Scholar
Xia, L.-Y., Wang, W.-L., Wang, S.-H., Huang, Y.-L. & Shan, S. (2009). Acta Cryst. E65, o1899. Web of Science CrossRef IUCr Journals Google Scholar
Zhang, M.-L. & Cai, H.-M. (2008). Jiangxi Shifan Daxue Xuebao Ziran Kexueban, 32, 657-661 Google Scholar
Zhang, M.-L., Gao, X.-M., Wang, D.-J., Guo, L. & Wang, J.-W. (2008). Z. Kristallogr. New Cryst. Struct. 223, 173–174. Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

IUCrDATA

ISSN: 2414-3146

Volume 3| Part 12| December 2018| x181630

https://doi.org/10.1107/S2414314618016309

Open

access

Format		BIBTeX
		EndNote
		RefMan
		Refer
		Medline
		CIF
		SGML
		Plain Text

Format		BIBTeX
		EndNote
		RefMan
		Refer
		Medline
		CIF
		SGML
		Plain Text

Search IUCr Journals		doi		Advanced search
Author		volume	page

organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Polar crystal of vanillylformamide through replacement of the alkene by an isosteric formamide group

Structure description

Synthesis and crystallization

Refinement

Structural data

Funding information

References

organic compounds