N-Acryloyl glycinamide

Seuring, J.; Agarwal, S.; Harms, K.

doi:10.1107/S1600536811029758

organic compounds

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ISSN: 2056-9890

Volume 67| Part 8| August 2011| Page o2170

doi:10.1107/S1600536811029758

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N-Acryloyl glycinamide

Jan Seuring,^a Seema Agarwal ^a ^* and Klaus Harms ^a ^*

^aPhilipps Universität Marburg, Fachbereich Chemie, Hans-Meerwein-Strasse, D-35032 Marburg, Germany
^*Correspondence e-mail: agarwal@staff.uni-marburg.de, klaus.harms@chemie.uni-marburg.de

(Received 12 July 2011; accepted 22 July 2011; online 30 July 2011)

The molecule of the title compound [systematic name: N-(carbamoylmethyl)prop-2-enamide], C₅H₈N₂O₂, which can be radically polymerized to polymers with thermoresponsive behavior in aqueous solution, consists of linked essentially planar acrylamide and amide segments [maximum deviations = 0.054 (1) and 0.009 (1) Å] with an angle of 81.36 (7)° between their mean planes. In the crystal, N—H⋯O hydrogen bonding leads to an infinite two-dimensional network along (100).

Related literature

For the first preparation of the title compound, see: Haas & Schuler (1964 ). For the properties of polymers of the title compound in aquous solution, see: Haas et al. (1967 , 1970a ,b ,c ,d ); Marstokk et al. (1998 ); Nagaoka et al. (2007 ); Ohnishi et al. (2007 ); Seuring & Agarwal (2010 ); Glatzel et al. (2010 ). For the structure of the related compound, 2-(2-acrylamidoacetamido)acetic acid monohydrate, see Gao et al. (2007 ).

Experimental

Crystal data

C₅H₈N₂O₂
M_r = 128.13
Monoclinic, P 2₁ /c
a = 15.938 (2) Å
b = 4.8055 (4) Å
c = 8.4920 (12) Å
β = 98.109 (11)°
V = 643.91 (14) Å³
Z = 4
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 100 K
0.23 × 0.19 × 0.09 mm

Data collection

Stoe IPDS 2T diffractometer
Absorption correction: integration (X-RED; Stoe & Cie, 2006 ) T_min = 0.991, T_max = 0.997
6001 measured reflections
1362 independent reflections
1065 reflections with I > 2σ(I)
R_int = 0.049

Refinement

R[F² > 2σ(F²)] = 0.032
wR(F²) = 0.085
S = 0.97
1362 reflections
115 parameters
All H-atom parameters refined
Δρ_max = 0.18 e Å⁻³
Δρ_min = −0.15 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N5—H5⋯O4ⁱ	0.850 (19)	2.062 (19)	2.8946 (14)	166.3 (15)
N8—H8B⋯O9ⁱⁱ	0.881 (17)	2.081 (17)	2.9494 (14)	168.2 (15)
N8—H8A⋯O9ⁱⁱⁱ	0.927 (18)	1.971 (18)	2.8855 (14)	168.6 (16)
Symmetry codes: (i) x, y+1, z; (ii) $[-x+1, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ ; (iii) $[x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ .

Data collection: X-AREA (Stoe & Cie, 2006); cell refinement: X-AREA; data reduction: X-AREA; program(s) used to solve structure: SIR92 (Altomare et al., 1994 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: DIAMOND (Brandenburg, 2007 ); software used to prepare material for publication: publCIF (Westrip, 2010 ), PLATON (Spek, 2009 ) and WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811029758/sj5179sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811029758/sj5179Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811029758/sj5179Isup3.cml

checkCIF report

Comment top

N-acryloyl glycinamide was first synthesized by Haas and Schuler (1964). It can be polymerized radically to obtain polymers that exhibit thermoresponsive behavior in aqueous solution. The polymers show gelatin-like thermoreversible gelation (Haas & Schuler, 1964; Haas et al., 1967, 1970a, 1970b, 1970c, 1970d; Marstokk et al., 1998; Seuring & Agarwal, 2010; Glatzel et al., 2010) and an upper critical solution temperature (Seuring & Agarwal, 2010; Ohnishi et al., 2007; Nagaoka et al., 2007) in water. These phenomena rely on intermolecular hydrogen bonding. Therefore, investigating the intermolecular hydrogen bonding between monomer units in the crystal may contribute to the understanding of interpolymer interactions.

The molecular structure of the title compound shows two planar parts with C1, C2, C3, O4, N5, C6 and C6, C7, N8, O9 in plane. The angle between these mean planes is 81.36 (7)°. In the packing the molecule forms three hydrogen bonds to three different neighbouring molecules. For details see Table 1. The intermolecular N5—H5···O4ⁱ contacts form an infinite chain in the (0 1 0) direction. Two of these chains are linked via N8—H8A···O9ⁱⁱⁱ and N8—H8B···O9ⁱⁱ interactions, respectively (symmetry codes: (i) x, y + 1, z; (ii) -x + 1, y - 1/2, -z + 3/2; (iii) x, -y + 1/2, z + 1/2). Herein the N8—H8A···O9ⁱⁱⁱ hydrogen bonds form a second chain with direction (0 0 1), and hydrogen bonded rings are generated. In conclusion, a two dimensional hydrogen bond network has been formed with the hydrophobic tails of the molecules as border planes.

For the crystal structure of a related compound, 2-(2-acrylamidoacetamido)acetic acid monohydrate, see Gao et al. (2007).

Related literature top

For the first preparation of the title compound, see: Haas & Schuler (1964). For the properties of polymers of the title compound in aquous solution, see: Glatzel et al. (2010); Haas et al. (1967, 1970a,b,c,d); Marstokk et al. (1998); Nagaoka et al. (2007); Ohnishi et al. (2007); Seuring & Agarwal (2010). For the structure of the related compound, 2-(2-acrylamidoacetamido)acetic acid monohydrate, see Gao et al. (2007).

Experimental top

N-acryloyl glycinamide has been prepared according to the route of Haas and Schuler (1964). However, reagent ratios, workup and purification have been modified as follows.

In a 1 l three-necked round-bottom flask equipped with a mechanical stirrer glycinamide hydrochloride (23.11 g, 209 mmol) and potassium carbonate (56.7 g, 410 mmol) were dissolved in 125 ml of water. The solution was cooled in an ice bath and acryloyl chloride (16.65 ml, 205 mmol) dissolved in 250 ml of diethylether was added dropwise over 30 min with fast stirring (300 rpm). The suspension was further stirred at RT for 2 h. The diethylether was removed by rotary evaporation at 35 °C. The remaining aqueous phase was freeze dried. The crude brittle solid was extracted with acetone (6 times, 500 ml acetone, 40 °C, stirring for at least 15 min). Insoluble potassium salts were filtered off and the acetone was removed by rotary evaporation at 35 °C. 22.7 g (85%) of crude product were obtained. The crude product was dissolved in an eluent mixture of methanol and dichloromethane (v/v = 1/4, 600 ml) by heating to reflux once. The solution was filtered to remove polymeric impurities and purified by column chromatography (d = 9 cm, 900 g silica, porosity 60 Å, 0.063–0.2 mm mesh size, TLC: R_f(N-acryloyl glycinamide) = 0.40) to obtain 21.3 g (80%) of product which was recrystallized from 240 ml of a mixture of methanol and acetone (v/v = 1/2) to yield 15.3 g (57%) of colorless needle-like crystals.

For obtaining crystals that are suitable for X-ray analysis a small fraction of purified N-acryloyl glycinamide was again recrystallized from a dilute solution in 2-propanol.

Computing details top

Data collection: X-AREA (Stoe & Cie, 2006); cell refinement: X-AREA (Stoe & Cie, 2006); data reduction: X-AREA (Stoe & Cie, 2006); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2007); software used to prepare material for publication: publCIF (Westrip, 2010), PLATON (Spek, 2009) and WinGX (Farrugia, 1999).

Figures top

	Fig. 1. View of the crystal structure of the title compund. The thermal ellipsoids are drawn at 50% probability level. Dashed lines indicate hydrogen bonding contacts.
	Fig. 2. Two dimensional hydrogen bond network with plane direction (1 0 0). Dashed lines indicate hydrogen bonds.

N-(Carbamoylmethyl)prop-2-enamide top

Crystal data top

C₅H₈N₂O₂	F(000) = 272
M_r = 128.13	D_x = 1.322 Mg m⁻³
Monoclinic, P2₁/c	Melting point: 143 K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71073 Å
a = 15.938 (2) Å	Cell parameters from 7769 reflections
b = 4.8055 (4) Å	θ = 2.6–27°
c = 8.4920 (12) Å	µ = 0.10 mm⁻¹
β = 98.109 (11)°	T = 100 K
V = 643.91 (14) Å³	Plate, colourless
Z = 4	0.23 × 0.19 × 0.09 mm

Data collection top

Stoe IPDS 2T diffractometer	1362 independent reflections
Radiation source: fine-focus sealed tube	1065 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.049
Detector resolution: 6.67 pixels mm^-1	θ_max = 26.8°, θ_min = 2.6°
rotation method scans	h = −20→17
Absorption correction: integration (X-RED; Stoe & Cie, 2006)	k = −6→6
T_min = 0.991, T_max = 0.997	l = −10→10
6001 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F² > 2σ(F²)] = 0.032	All H-atom parameters refined
wR(F²) = 0.085	w = 1/[σ²(F_o²) + (0.0548P)²] where P = (F_o² + 2F_c²)/3
S = 0.97	(Δ/σ)_max < 0.001
1362 reflections	Δρ_max = 0.18 e Å⁻³
115 parameters	Δρ_min = −0.15 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.032 (7)

Crystal data top

C₅H₈N₂O₂	V = 643.91 (14) Å³
M_r = 128.13	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 15.938 (2) Å	µ = 0.10 mm⁻¹
b = 4.8055 (4) Å	T = 100 K
c = 8.4920 (12) Å	0.23 × 0.19 × 0.09 mm
β = 98.109 (11)°

Data collection top

Stoe IPDS 2T diffractometer	1362 independent reflections
Absorption correction: integration (X-RED; Stoe & Cie, 2006)	1065 reflections with I > 2σ(I)
T_min = 0.991, T_max = 0.997	R_int = 0.049
6001 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.032	0 restraints
wR(F²) = 0.085	All H-atom parameters refined
S = 0.97	Δρ_max = 0.18 e Å⁻³
1362 reflections	Δρ_min = −0.15 e Å⁻³
115 parameters

Special details top

Experimental. DSC (rate of heating = 10 K min^-1): T_m = 143 °C. IR (ATR): ν= 3380 (m, NH), 3312 (s, NH), 3187 (m, NH), 1652 (vs, C=O), 1621 (vs, C=O), 1551 (vs, NH) cm^{-1. 1}H NMR (300 MHz, D₂O): δ = 3.93 (s, 2H, N–CH₂–CONH₂), 5.77 [dd, J(doublet 1) = 2.0 Hz, J(doublet 2) = 9.5 Hz, 1H, H_olef.], 6.20 [dd, J(doublet 1) = 2.0 Hz, J(doublet 2) = 17.1 Hz, 1H, H_olef.], 6.29 [dd, J(doublet 1) = 9.5 Hz, J(doublet 2) = 17.2 Hz, 1H, H_olef.]. ¹³C NMR (75 MHz, D₂O): δ = 42.7 (–N—CH₂–), 128.8 (C_olef.), 130.0 (C_olef.), 169.6 (–CO–), 174.8 (CO–). Flame emission spectroscopy: potassium content 5 p.p.m.

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

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > 2σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

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

	x	y	z	U_iso*/U_eq
C1	0.91738 (9)	0.4644 (3)	0.66968 (16)	0.0334 (3)
C2	0.87077 (8)	0.6065 (3)	0.75755 (15)	0.0269 (3)
C3	0.80276 (7)	0.4732 (3)	0.83438 (13)	0.0218 (3)
C6	0.68733 (7)	0.5421 (3)	0.98560 (13)	0.0229 (3)
C7	0.61296 (7)	0.4355 (3)	0.86952 (13)	0.0209 (3)
N5	0.75513 (6)	0.6473 (2)	0.90665 (12)	0.0221 (3)
N8	0.56460 (7)	0.2477 (2)	0.92691 (12)	0.0271 (3)
O4	0.79110 (6)	0.21891 (18)	0.83202 (10)	0.0280 (2)
O9	0.59828 (5)	0.52628 (19)	0.73164 (9)	0.0248 (2)
H1A	0.9069 (10)	0.273 (4)	0.6562 (19)	0.038 (4)*
H1B	0.9623 (10)	0.553 (4)	0.620 (2)	0.041 (4)*
H2	0.8770 (10)	0.802 (4)	0.7774 (18)	0.036 (4)*
H5	0.7628 (10)	0.822 (4)	0.8996 (19)	0.034 (4)*
H6A	0.7081 (8)	0.395 (3)	1.0551 (17)	0.023 (3)*
H6B	0.6661 (9)	0.697 (3)	1.0471 (17)	0.025 (3)*
H8A	0.5799 (10)	0.181 (4)	1.029 (2)	0.042 (4)*
H8B	0.5176 (11)	0.194 (4)	0.867 (2)	0.040 (4)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0316 (7)	0.0359 (8)	0.0336 (7)	0.0022 (6)	0.0078 (5)	0.0017 (6)
C2	0.0260 (6)	0.0247 (7)	0.0300 (6)	−0.0003 (5)	0.0039 (5)	0.0015 (5)
C3	0.0246 (6)	0.0198 (6)	0.0201 (5)	0.0000 (5)	0.0001 (4)	0.0001 (4)
C6	0.0261 (6)	0.0237 (6)	0.0189 (6)	−0.0002 (5)	0.0028 (4)	−0.0010 (5)
C7	0.0231 (6)	0.0211 (6)	0.0193 (5)	0.0030 (5)	0.0058 (4)	−0.0008 (4)
N5	0.0244 (5)	0.0177 (6)	0.0246 (5)	−0.0012 (4)	0.0040 (4)	−0.0010 (4)
N8	0.0286 (5)	0.0318 (7)	0.0204 (5)	−0.0076 (4)	0.0020 (4)	0.0030 (4)
O4	0.0361 (5)	0.0180 (5)	0.0304 (5)	−0.0008 (4)	0.0065 (4)	−0.0011 (4)
O9	0.0273 (4)	0.0291 (5)	0.0178 (4)	0.0006 (4)	0.0028 (3)	0.0025 (3)

Geometric parameters (Å, º) top

C1—C2	1.3160 (19)	C6—C7	1.5198 (16)
C1—H1A	0.937 (18)	C6—H6A	0.950 (15)
C1—H1B	0.981 (18)	C6—H6B	0.994 (15)
C2—C3	1.4867 (17)	C7—O9	1.2405 (13)
C2—H2	0.956 (18)	C7—N8	1.3235 (16)
C3—O4	1.2360 (15)	N5—H5	0.850 (19)
C3—N5	1.3356 (16)	N8—H8A	0.927 (18)
C6—N5	1.4412 (15)	N8—H8B	0.881 (17)

C2—C1—H1A	118.2 (10)	N5—C6—H6B	108.4 (8)
C2—C1—H1B	121.6 (10)	C7—C6—H6B	107.4 (8)
H1A—C1—H1B	120.2 (15)	H6A—C6—H6B	110.1 (11)
C1—C2—C3	122.01 (13)	O9—C7—N8	123.05 (11)
C1—C2—H2	123.8 (10)	O9—C7—C6	121.30 (11)
C3—C2—H2	114.2 (10)	N8—C7—C6	115.62 (10)
O4—C3—N5	122.19 (11)	C3—N5—C6	120.42 (11)
O4—C3—C2	122.42 (11)	C3—N5—H5	119.2 (11)
N5—C3—C2	115.39 (11)	C6—N5—H5	120.2 (11)
N5—C6—C7	112.57 (9)	C7—N8—H8A	119.6 (11)
N5—C6—H6A	109.3 (8)	C7—N8—H8B	118.6 (11)
C7—C6—H6A	108.9 (8)	H8A—N8—H8B	121.8 (15)

C1—C2—C3—O4	6.58 (19)	O4—C3—N5—C6	−0.03 (16)
C1—C2—C3—N5	−173.59 (12)	C2—C3—N5—C6	−179.87 (10)
N5—C6—C7—O9	−26.19 (17)	C7—C6—N5—C3	−70.81 (14)
N5—C6—C7—N8	155.59 (11)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N5—H5···O4ⁱ	0.850 (19)	2.062 (19)	2.8946 (14)	166.3 (15)
N8—H8B···O9ⁱⁱ	0.881 (17)	2.081 (17)	2.9494 (14)	168.2 (15)
N8—H8A···O9ⁱⁱⁱ	0.927 (18)	1.971 (18)	2.8855 (14)	168.6 (16)

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

Experimental details

Crystal data
Chemical formula	C₅H₈N₂O₂
M_r	128.13
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	100
a, b, c (Å)	15.938 (2), 4.8055 (4), 8.4920 (12)
β (°)	98.109 (11)
V (Å³)	643.91 (14)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.23 × 0.19 × 0.09

Data collection
Diffractometer	Stoe IPDS 2T diffractometer
Absorption correction	Integration (X-RED; Stoe & Cie, 2006)
T_min, T_max	0.991, 0.997
No. of measured, independent and observed [I > 2σ(I)] reflections	6001, 1362, 1065
R_int	0.049
(sin θ/λ)_max (Å⁻¹)	0.634

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.032, 0.085, 0.97
No. of reflections	1362
No. of parameters	115
H-atom treatment	All H-atom parameters refined
Δρ_max, Δρ_min (e Å⁻³)	0.18, −0.15

Computer programs: X-AREA (Stoe & Cie, 2006), SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 2007), publCIF (Westrip, 2010), PLATON (Spek, 2009) and WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N5—H5···O4ⁱ	0.850 (19)	2.062 (19)	2.8946 (14)	166.3 (15)
N8—H8B···O9ⁱⁱ	0.881 (17)	2.081 (17)	2.9494 (14)	168.2 (15)
N8—H8A···O9ⁱⁱⁱ	0.927 (18)	1.971 (18)	2.8855 (14)	168.6 (16)

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

Acknowledgements

We acknowledge financial support from Philipps-Universität Marburg, Germany.

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