(2Z)-Methyl 2-(2-amino-1,3-thia­zol-4-yl)-2-(methoxy­imino)ethano­ate

Abstract

In the title compound, C₇H₉N₃O₃S, the planes of the 2-amino-1,3-thia­zol-4-yl and the methyl ester groups are oriented at a dihedral angle of 67.06 (7)°. In the crystal, inversion dimers linked by pairs of N—H⋯N hydrogen bonds occur, forming R ₂ ²(8) ring motifs. The dimers are inter­linked by N—H⋯O hydrogen bonds, resulting in sheets propagating in the ac plane.

Related literature

For a related structure, see: Laurent et al. (1981 ▶). For background to the use of the title compound in organic synthesis, see: Khanna et al. (1999 ▶). For graph-set notation, see: Bernstein et al. (1995 ▶);

Experimental

Crystal data

• C₇H₉N₃O₃S

• M _r = 215.23

• Monoclinic,

• a = 7.8096 (4) Å

• b = 8.1994 (5) Å

• c = 15.6247 (9) Å

• β = 92.936 (2)°

• V = 999.20 (10) ų

• Z = 4

• Mo Kα radiation

• μ = 0.31 mm⁻¹

• T = 296 K

• 0.25 × 0.20 × 0.18 mm

Data collection

• Bruker Kappa APEXII CCD diffractometer

• Absorption correction: multi-scan (SADABS; Bruker, 2005 ▶) T _min = 0.931, T _max = 0.945

• 9949 measured reflections

• 2295 independent reflections

• 1696 reflections with I > 2σ(I)

• R _int = 0.028

Refinement

• R[F ² > 2σ(F ²)] = 0.040

• wR(F ²) = 0.120

• S = 1.03

• 2295 reflections

• 135 parameters

• H atoms treated by a mixture of independent and constrained refinement

• Δρ_max = 0.26 e Å⁻³

• Δρ_min = −0.16 e Å⁻³

Data collection: APEX2 (Bruker, 2007 ▶); cell refinement: SAINT (Bruker, 2007 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 (Farrugia, 1997 ▶) and PLATON (Spek, 2009 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶) and PLATON.

Supplementary Material

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

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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2A⋯O1i	0.83 (3)	2.28 (2)	3.058 (2)	156 (2)
N2—H2B⋯N1ii	0.84 (3)	2.20 (3)	3.024 (2)	166 (3)

Symmetry codes: (i) ; (ii) .

supplementary crystallographic information

Comment

2-Mercapto-benzothiazolyl-(Z)-2-(2-aminothiazol-4-yl)-2-methoxyimino acetate (MAEM) is a standard acylating agent for the preparation of cephalosporins (Khanna et al., 1999). The title compound (I), (Fig 1), is prepared as an intermediate for derivitaziation.

The crystal structure of (II) Ethyl 2-amino-α-(E-methoxyimino)-4-thiazoleacetate (Laurent et al., 1981) has been published. (I) differs from (II) due to the methoxy group attached with carbonyl instead of ethoxy moiety.

The title compound is dimerized due to the intermolecular H-bonding of N—H···N type forming R₂²(8) ring motifs (Bernstein et al., 1995). The dimers are further linked with each other through the intermolecular H-bonding of N—H···O type (Table 1), (Fig. 2). The five membered ring along with NH₂ A (C1/C2/S1/C3/N1/N2), methyl ester group B (O1/C5/O2/C6) and the group C (C4/N3/O3/C7) are planar. The dihedral angles between A/B, A/C and B/C have values of 67.06 (7), 9.21 (16) and 71.67 (11)°, respectively.

Experimental

2-Mercapto-benzothiazolyl-(Z)-2-(2-aminothiazol-4-yl)-2-methoxyimino acetate (0.2 g, 1.4 mmol) was dissolved in methanol (5 ml) and stirred for 1 h at 303 K. Yellow prisms of (I) were obtained through slow evaporation after five days.

Refinement

The coordinates of H-atoms of NH₂ group were refined. Other H atoms were positioned geometrically, with C—H = 0.93 and 0.96 Å for aryl and methyl H, respectively and constrained to ride on their parent atoms, with U_iso(H) = xU_eq(C, N), where x = 1.5 for methyl and 1.2 for other H atoms.

Figures

Fig. 1.

View of (I) with displacement ellipsoids drawn at the 50% probability level. H-atoms are shown by small spheres of arbitrary radius.

Fig. 2.

The partial packing of (I) which shows that molecules form dimers and the dimers are interlinked forming two dimensional polymeric sheets.

Crystal data

C7H9N3O3S	F(000) = 448
Mr = 215.23	Dx = 1.431 Mg m−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 2295 reflections
a = 7.8096 (4) Å	θ = 2.6–27.5°
b = 8.1994 (5) Å	µ = 0.31 mm−1
c = 15.6247 (9) Å	T = 296 K
β = 92.936 (2)°	Prism, yellow
V = 999.20 (10) Å3	0.25 × 0.20 × 0.18 mm
Z = 4

Data collection

Bruker Kappa APEXII CCD diffractometer	2295 independent reflections
Radiation source: fine-focus sealed tube	1696 reflections with I > 2σ(I)
graphite	Rint = 0.028
Detector resolution: 7.50 pixels mm-1	θmax = 27.5°, θmin = 2.6°
ω scans	h = −10→10
Absorption correction: multi-scan (SADABS; Bruker, 2005)	k = −8→10
Tmin = 0.931, Tmax = 0.945	l = −20→20
9949 measured reflections

Refinement

Refinement on F2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.120	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ2(Fo2) + (0.0635P)2 + 0.2265P] where P = (Fo2 + 2Fc2)/3
2295 reflections	(Δ/σ)max < 0.001
135 parameters	Δρmax = 0.26 e Å−3
0 restraints	Δρmin = −0.16 e Å−3

Special details

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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 > σ(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 (Ų)

	x	y	z	Uiso*/Ueq
S1	0.41857 (6)	0.20584 (8)	0.43460 (3)	0.0599 (2)
O1	0.04763 (18)	0.26609 (19)	0.13478 (9)	0.0637 (5)
O2	0.25926 (17)	0.08248 (18)	0.14230 (9)	0.0599 (5)
O3	−0.14991 (17)	−0.0224 (2)	0.17911 (8)	0.0606 (5)
N1	0.11714 (18)	0.0792 (2)	0.41045 (9)	0.0475 (5)
N2	0.2110 (2)	0.0993 (3)	0.55484 (11)	0.0719 (8)
N3	−0.06554 (18)	−0.0011 (2)	0.26002 (9)	0.0482 (5)
C1	0.1775 (2)	0.1176 (2)	0.33140 (11)	0.0419 (5)
C2	0.3342 (2)	0.1859 (3)	0.33191 (12)	0.0519 (6)
C3	0.2315 (2)	0.1199 (3)	0.47114 (12)	0.0483 (6)
C4	0.0712 (2)	0.0836 (2)	0.25360 (11)	0.0412 (5)
C5	0.1219 (2)	0.1552 (2)	0.17005 (11)	0.0452 (6)
C6	0.3165 (3)	0.1371 (4)	0.05994 (15)	0.0826 (10)
C7	−0.3004 (3)	−0.1162 (4)	0.18950 (16)	0.0913 (12)
H2	0.38901	0.21784	0.28319	0.0622*
H2A	0.288 (3)	0.129 (3)	0.5901 (17)	0.0863*
H2B	0.124 (4)	0.053 (3)	0.5734 (17)	0.0863*
H6A	0.24081	0.09504	0.01485	0.1240*
H6B	0.43070	0.09816	0.05256	0.1240*
H6C	0.31566	0.25411	0.05803	0.1240*
H7A	−0.27198	−0.21154	0.22295	0.1370*
H7B	−0.34834	−0.14852	0.13428	0.1370*
H7C	−0.38262	−0.05196	0.21829	0.1370*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
S1	0.0470 (3)	0.0858 (4)	0.0465 (3)	−0.0188 (3)	−0.0024 (2)	0.0058 (3)
O1	0.0605 (9)	0.0762 (10)	0.0548 (9)	0.0119 (8)	0.0062 (7)	0.0219 (8)
O2	0.0583 (8)	0.0742 (10)	0.0486 (8)	0.0134 (7)	0.0177 (6)	0.0089 (7)
O3	0.0514 (7)	0.0897 (11)	0.0403 (7)	−0.0193 (7)	−0.0009 (5)	0.0000 (7)
N1	0.0366 (7)	0.0672 (10)	0.0385 (8)	−0.0026 (7)	0.0012 (6)	0.0057 (7)
N2	0.0506 (10)	0.1262 (19)	0.0386 (9)	−0.0213 (11)	−0.0016 (7)	0.0093 (10)
N3	0.0444 (8)	0.0626 (10)	0.0374 (8)	−0.0034 (7)	0.0015 (6)	−0.0006 (7)
C1	0.0397 (8)	0.0468 (10)	0.0392 (9)	0.0019 (7)	0.0019 (7)	0.0054 (8)
C2	0.0480 (10)	0.0666 (12)	0.0410 (9)	−0.0114 (9)	0.0023 (8)	0.0065 (9)
C3	0.0383 (8)	0.0634 (12)	0.0431 (10)	−0.0017 (8)	0.0019 (7)	0.0053 (9)
C4	0.0377 (8)	0.0475 (10)	0.0385 (9)	0.0033 (7)	0.0039 (6)	0.0016 (8)
C5	0.0415 (9)	0.0546 (11)	0.0394 (9)	−0.0019 (8)	0.0010 (7)	0.0015 (8)
C6	0.0799 (16)	0.112 (2)	0.0588 (14)	0.0138 (15)	0.0323 (12)	0.0181 (14)
C7	0.0640 (14)	0.142 (3)	0.0674 (15)	−0.0480 (16)	−0.0010 (12)	−0.0012 (16)

Geometric parameters (Å, °)

S1—C2	1.7109 (19)	N2—H2B	0.84 (3)
S1—C3	1.7442 (18)	C1—C2	1.346 (2)
O1—C5	1.198 (2)	C1—C4	1.463 (2)
O2—C5	1.320 (2)	C4—C5	1.503 (2)
O2—C6	1.454 (3)	C2—H2	0.9300
O3—N3	1.4062 (19)	C6—H6A	0.9600
O3—C7	1.421 (3)	C6—H6B	0.9600
N1—C1	1.381 (2)	C6—H6C	0.9600
N1—C3	1.312 (2)	C7—H7A	0.9600
N2—C3	1.336 (3)	C7—H7B	0.9600
N3—C4	1.282 (2)	C7—H7C	0.9600
N2—H2A	0.83 (3)
C2—S1—C3	88.83 (9)	O1—C5—O2	125.06 (16)
C5—O2—C6	116.32 (17)	O1—C5—C4	123.60 (15)
N3—O3—C7	108.47 (15)	O2—C5—C4	111.32 (14)
C1—N1—C3	109.73 (15)	S1—C2—H2	125.00
O3—N3—C4	110.53 (14)	C1—C2—H2	125.00
H2A—N2—H2B	118 (3)	O2—C6—H6A	109.00
C3—N2—H2B	122.2 (18)	O2—C6—H6B	109.00
C3—N2—H2A	119.5 (17)	O2—C6—H6C	109.00
C2—C1—C4	124.15 (16)	H6A—C6—H6B	109.00
N1—C1—C4	119.64 (14)	H6A—C6—H6C	109.00
N1—C1—C2	116.21 (16)	H6B—C6—H6C	109.00
S1—C2—C1	110.60 (14)	O3—C7—H7A	109.00
S1—C3—N1	114.63 (14)	O3—C7—H7B	109.00
S1—C3—N2	121.05 (14)	O3—C7—H7C	109.00
N1—C3—N2	124.33 (17)	H7A—C7—H7B	109.00
C1—C4—C5	118.93 (14)	H7A—C7—H7C	109.00
N3—C4—C1	118.53 (15)	H7B—C7—H7C	109.00
N3—C4—C5	122.49 (15)
C3—S1—C2—C1	−0.42 (17)	O3—N3—C4—C5	3.3 (2)
C2—S1—C3—N1	0.46 (18)	N1—C1—C2—S1	0.3 (2)
C2—S1—C3—N2	−179.5 (2)	C4—C1—C2—S1	−179.86 (13)
C6—O2—C5—O1	−3.7 (3)	N1—C1—C4—N3	−9.3 (2)
C6—O2—C5—C4	177.57 (17)	N1—C1—C4—C5	168.00 (15)
C7—O3—N3—C4	−179.82 (18)	C2—C1—C4—N3	170.87 (19)
C3—N1—C1—C2	0.0 (2)	C2—C1—C4—C5	−11.8 (3)
C3—N1—C1—C4	−179.81 (17)	N3—C4—C5—O1	70.4 (2)
C1—N1—C3—S1	−0.4 (2)	N3—C4—C5—O2	−110.87 (18)
C1—N1—C3—N2	179.6 (2)	C1—C4—C5—O1	−106.8 (2)
O3—N3—C4—C1	−179.50 (14)	C1—C4—C5—O2	71.92 (19)

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···O1i	0.83 (3)	2.28 (2)	3.058 (2)	156 (2)
N2—H2B···N1ii	0.84 (3)	2.20 (3)	3.024 (2)	166 (3)

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