5-(1,3-Benzo­thia­zol-2-yl­imino­methyl)-2,2-di­methyl-1,3-dioxane-4,6-dione

The title compound, C₁₄H₁₂N₂O₄S, has a supramolecular structure consisting of base-paired dimers with an R²₂(12) motif formed by a centrosymmetrically related pair of N—H...O hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 150 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.045
• wR factor = 0.123
• Data-to-parameter ratio = 17.7

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level A:



REFLT_03
         From the CIF: _diffrn_reflns_theta_max           30.50
         From the CIF: _reflns_number_total               3392
         TEST2: Reflns within _diffrn_reflns_theta_max
         Count of symmetry unique reflns         4026
         Completeness (_total/calc)             84.25%
          Alert A: < 85% complete (theta max?)


 Alert Level C:



PLAT_320  Alert C Check Hybridisation of  S(51)  in main residue          ?


 1 Alert Level A = Potentially serious problem

 0 Alert Level B = Potential problem

 1 Alert Level C = Please check

---

S1. Comment

We have focused on benzothiazole derivatives, which have shown diverse applications, as analgesics (Mehra et al., 1980), anti-inflammatory agents, antineoplasics (Cheng et al., 1993) and antimicrobial agents (Mehra et al., 1980; El-Shaaer et al., 1998), in our search for biological active molecules. Benzothiazole derivatives have been prepared by a known reaction (Quiroga et al., 1998). The title compound, (I), was prepared by condensation of Meldrum's acid, 2,2-dimethyl-1,3-dioxane-4,6-dione), 2-aminobenzothiazole and trimethyl orthoformate.

The supramolecular structure consists of base-paired dimers with an R²₂(12) motif (Bernstein et al., 1995), formed by the N51—H51···O61ⁱ hydrogen bond which is repeated across the centre at (1,1/2,1).

Geometric parameters are given in Table 1 and details of hydrogen bonds are given in Table 2. Fig. 1 shows a view of the molecule.

Examination of the structure with PLATON (Spek, 2000) showed that there were no solvent-accessible voids in the crystal lattice.

S2. Experimental

A mixture of the Meldrum's acid (6.94 mmol) and trimethyl orthoformate (34.7 mmol) was heated to reflux for 2.5 h, then 2-aminobenzothiazole (6.94 mmol) was added and the mixture was heated for a further 5 min. The title compound precipitated and was separated by filtration and was recrystallized from a dimethylformamide–ethanol mixture, affording crystals suitable for X-ray diffraction (m.p. 480–481 K, yield: 60%).

S3. Refinement

H atoms were treated as riding with C—H distances in the range 0.95–0.98 Å and an N—H distance of 0.88 Å.

Computing details

Data collection: KappaCCD Server Software (Nonius, 1997); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976) and PLATON (Spek, 2000); software used to prepare material for publication: SHELXL97 and WORDPERFECT macro PRPKAPPA (Ferguson, 1999).

Figures

Fig. 1. A view of the title molecule with the atomic numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.

5-(1,3-Benzothiazol-2-yliminomethyl)-2,2-dimethyl-1,3-dioxane-4,6-dione

Crystal data

C14H12N2O4S	Dx = 1.526 Mg m^−3
Mr = 304.32	Melting point: 480 K
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 6.3459 (13) Å	Cell parameters from 6132 reflections
b = 19.235 (4) Å	θ = 1.0–30.5°
c = 11.144 (2) Å	µ = 0.26 mm^−1
β = 103.07 (3)°	T = 150 K
V = 1325.0 (5) Å^3	Needle, orange
Z = 4	0.38 × 0.05 × 0.05 mm
F(000) = 632

Data collection

KappaCCD diffractometer	3392 independent reflections
Radiation source: fine-focus sealed X-ray tube	2645 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.081
ϕ and ω scans with κ offsets	θmax = 30.5°, θmin = 2.1°
Absorption correction: multi-scan (DENZO-SMN; Otwinowski & Minor, 1997)	h = −9→8
Tmin = 0.908, Tmax = 0.987	k = −22→27
12128 measured reflections	l = −13→15

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.045	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.123	H-atom parameters constrained
S = 1.08	w = 1/[σ^2(Fo^2) + (0.0684P)^2 + 0.1432P] where P = (Fo^2 + 2Fc^2)/3
3392 reflections	(Δ/σ)max = 0.001
192 parameters	Δρmax = 0.42 e Å^−3
0 restraints	Δρmin = −0.52 e Å^−3

Special details

Experimental. The program DENZO-SMN (Otwinowski & Minor, 1997) uses a scaling algorithm (Fox & Holmes, 1966) which effectively corrects for absorption effects. High redundancy data were used in the scaling program hence the 'multi-scan' code word was used. no transmission coefficients are available from the program (only scale factors for each frame). The scale factors in the experimental table are calculated from the 'size' command in the SHELXL97 input file.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1	1.30516 (18)	0.33588 (5)	1.01481 (10)	0.0176 (3)
C2	1.2845 (3)	0.26447 (8)	1.05018 (14)	0.0160 (3)
C21	1.4987 (3)	0.22996 (9)	1.05657 (16)	0.0214 (4)
C22	1.2121 (3)	0.26217 (9)	1.17025 (14)	0.0211 (4)
O3	1.13153 (17)	0.22842 (6)	0.95487 (10)	0.0175 (3)
C4	0.9419 (3)	0.25966 (8)	0.90183 (14)	0.0164 (3)
O41	0.80048 (19)	0.22442 (6)	0.83965 (11)	0.0232 (3)
C5	0.9286 (2)	0.33450 (8)	0.92197 (14)	0.0155 (3)
C6	1.1201 (2)	0.37333 (8)	0.97893 (13)	0.0149 (3)
O61	1.12713 (19)	0.43617 (6)	0.99149 (10)	0.0200 (3)
C51	0.7346 (3)	0.36591 (8)	0.87199 (14)	0.0164 (3)
N51	0.6866 (2)	0.43317 (7)	0.87370 (12)	0.0166 (3)
S51	0.41125 (6)	0.54339 (2)	0.82927 (4)	0.01825 (14)
C52	0.4810 (3)	0.45697 (8)	0.81356 (14)	0.0159 (3)
N53	0.3390 (2)	0.41683 (7)	0.74643 (12)	0.0178 (3)
C54	0.1509 (3)	0.45444 (8)	0.70129 (15)	0.0166 (3)
C55	−0.0374 (3)	0.42851 (9)	0.62415 (15)	0.0226 (4)
C56	−0.2110 (3)	0.47256 (10)	0.58642 (17)	0.0259 (4)
C57	−0.2004 (3)	0.54215 (9)	0.62270 (17)	0.0254 (4)
C58	−0.0151 (3)	0.56924 (9)	0.69764 (15)	0.0206 (4)
C59	0.1594 (3)	0.52439 (8)	0.73635 (14)	0.0164 (3)
H21A	1.4915	0.1815	1.0824	0.032*
H21B	1.6113	0.2545	1.1163	0.032*
H21C	1.5332	0.2314	0.9752	0.032*
H22A	1.0651	0.2809	1.1577	0.032*
H22B	1.3105	0.2902	1.2321	0.032*
H22C	1.2136	0.2140	1.1989	0.032*
H51A	0.6212	0.3362	0.8314	0.020*
H51	0.7842	0.4628	0.9126	0.020*
H55	−0.0456	0.3814	0.5982	0.027*
H56	−0.3404	0.4552	0.5347	0.031*
H57	−0.3226	0.5714	0.5954	0.030*
H58	−0.0069	0.6167	0.7219	0.025*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0176 (5)	0.0113 (6)	0.0220 (6)	−0.0004 (4)	0.0004 (5)	0.0039 (4)
C2	0.0187 (8)	0.0103 (7)	0.0171 (8)	0.0001 (6)	0.0000 (6)	0.0000 (6)
C21	0.0202 (8)	0.0186 (8)	0.0240 (9)	0.0030 (7)	0.0017 (7)	0.0011 (7)
C22	0.0298 (9)	0.0161 (8)	0.0171 (8)	0.0022 (7)	0.0047 (7)	0.0017 (6)
O3	0.0193 (6)	0.0114 (6)	0.0196 (6)	0.0014 (4)	−0.0002 (5)	−0.0022 (4)
C4	0.0180 (8)	0.0146 (8)	0.0163 (8)	0.0018 (6)	0.0035 (6)	0.0004 (6)
O41	0.0215 (6)	0.0173 (6)	0.0278 (6)	−0.0006 (5)	−0.0010 (5)	−0.0078 (5)
C5	0.0183 (8)	0.0126 (8)	0.0147 (7)	0.0005 (6)	0.0015 (6)	−0.0006 (6)
C6	0.0190 (8)	0.0135 (8)	0.0124 (7)	0.0008 (6)	0.0038 (6)	0.0017 (6)
O61	0.0237 (6)	0.0104 (6)	0.0242 (6)	−0.0010 (4)	0.0021 (5)	−0.0006 (4)
C51	0.0184 (7)	0.0147 (8)	0.0154 (7)	−0.0001 (6)	0.0019 (6)	−0.0010 (6)
N51	0.0172 (7)	0.0129 (7)	0.0177 (7)	0.0006 (5)	−0.0001 (5)	−0.0008 (5)
S51	0.0188 (2)	0.0114 (2)	0.0221 (2)	0.00052 (14)	−0.00051 (16)	−0.00246 (14)
C52	0.0202 (8)	0.0120 (8)	0.0151 (8)	0.0004 (6)	0.0030 (6)	0.0005 (6)
N53	0.0198 (7)	0.0138 (7)	0.0181 (7)	0.0014 (5)	0.0004 (5)	−0.0009 (5)
C54	0.0195 (8)	0.0142 (8)	0.0156 (8)	0.0010 (6)	0.0029 (6)	0.0019 (6)
C55	0.0254 (9)	0.0165 (8)	0.0232 (9)	−0.0009 (7)	−0.0004 (7)	−0.0013 (7)
C56	0.0194 (8)	0.0270 (9)	0.0265 (9)	−0.0021 (7)	−0.0046 (7)	0.0022 (7)
C57	0.0195 (8)	0.0264 (10)	0.0276 (9)	0.0060 (7)	0.0000 (7)	0.0060 (7)
C58	0.0236 (8)	0.0147 (8)	0.0233 (8)	0.0037 (7)	0.0047 (7)	0.0009 (7)
C59	0.0181 (8)	0.0154 (8)	0.0150 (8)	0.0001 (6)	0.0026 (6)	−0.0002 (6)

Geometric parameters (Å, º)

O1—C6	1.3583 (18)	C51—H51A	0.9500
O1—C2	1.4430 (18)	N51—C52	1.402 (2)
C2—O3	1.4439 (18)	N51—H51	0.8800
C2—C21	1.500 (2)	S51—C59	1.7355 (16)
C2—C22	1.511 (2)	S51—C52	1.7391 (15)
C21—H21A	0.9800	C52—N53	1.290 (2)
C21—H21B	0.9800	N53—C54	1.389 (2)
C21—H21C	0.9800	C54—C55	1.397 (2)
C22—H22A	0.9800	C54—C59	1.399 (2)
C22—H22B	0.9800	C55—C56	1.378 (2)
C22—H22C	0.9800	C55—H55	0.9500
O3—C4	1.3555 (18)	C56—C57	1.395 (3)
C4—O41	1.2097 (18)	C56—H56	0.9500
C4—C5	1.462 (2)	C57—C58	1.381 (2)
C5—C51	1.371 (2)	C57—H57	0.9500
C5—C6	1.445 (2)	C58—C59	1.393 (2)
C6—O61	1.2164 (19)	C58—H58	0.9500
C51—N51	1.330 (2)
C6—O1—C2	117.34 (12)	N51—C51—C5	127.59 (15)
O1—C2—O3	110.10 (11)	N51—C51—H51A	116.2
O1—C2—C21	107.27 (13)	C5—C51—H51A	116.2
O3—C2—C21	105.88 (12)	C51—N51—C52	120.14 (14)
O1—C2—C22	109.54 (12)	C51—N51—H51	119.9
O3—C2—C22	110.41 (13)	C52—N51—H51	119.9
C21—C2—C22	113.52 (14)	C59—S51—C52	87.69 (8)
C2—C21—H21A	109.5	N53—C52—N51	122.31 (14)
C2—C21—H21B	109.5	N53—C52—S51	118.05 (12)
H21A—C21—H21B	109.5	N51—C52—S51	119.64 (11)
C2—C21—H21C	109.5	C52—N53—C54	109.19 (13)
H21A—C21—H21C	109.5	N53—C54—C55	125.62 (14)
H21B—C21—H21C	109.5	N53—C54—C59	115.11 (14)
C2—C22—H22A	109.5	C55—C54—C59	119.26 (15)
C2—C22—H22B	109.5	C56—C55—C54	118.82 (16)
H22A—C22—H22B	109.5	C56—C55—H55	120.6
C2—C22—H22C	109.5	C54—C55—H55	120.6
H22A—C22—H22C	109.5	C55—C56—C57	121.22 (16)
H22B—C22—H22C	109.5	C55—C56—H56	119.4
C4—O3—C2	119.39 (12)	C57—C56—H56	119.4
O41—C4—O3	118.15 (14)	C58—C57—C56	121.05 (16)
O41—C4—C5	125.35 (14)	C58—C57—H57	119.5
O3—C4—C5	116.47 (13)	C56—C57—H57	119.5
C51—C5—C6	122.64 (14)	C57—C58—C59	117.52 (15)
C51—C5—C4	116.67 (14)	C57—C58—H58	121.2
C6—C5—C4	120.27 (14)	C59—C58—H58	121.2
O61—C6—O1	119.10 (14)	C58—C59—C54	122.13 (15)
O61—C6—C5	124.69 (14)	C58—C59—S51	127.93 (13)
O1—C6—C5	116.13 (13)	C54—C59—S51	109.94 (12)
C6—O1—C2—O3	52.11 (17)	C51—N51—C52—N53	−6.1 (2)
C6—O1—C2—C21	166.88 (13)	C51—N51—C52—S51	173.61 (12)
C6—O1—C2—C22	−69.48 (16)	C59—S51—C52—N53	0.74 (14)
O1—C2—O3—C4	−44.54 (17)	C59—S51—C52—N51	−179.02 (13)
C21—C2—O3—C4	−160.19 (13)	N51—C52—N53—C54	178.81 (14)
C22—C2—O3—C4	76.54 (16)	S51—C52—N53—C54	−0.94 (18)
C2—O3—C4—O41	−166.52 (13)	C52—N53—C54—C55	179.34 (16)
C2—O3—C4—C5	15.38 (19)	C52—N53—C54—C59	0.7 (2)
O41—C4—C5—C51	4.2 (2)	N53—C54—C55—C56	−179.64 (15)
O3—C4—C5—C51	−177.86 (13)	C59—C54—C55—C56	−1.0 (3)
O41—C4—C5—C6	−168.60 (15)	C54—C55—C56—C57	0.8 (3)
O3—C4—C5—C6	9.3 (2)	C55—C56—C57—C58	0.1 (3)
C2—O1—C6—O61	153.43 (13)	C56—C57—C58—C59	−0.6 (3)
C2—O1—C6—C5	−29.61 (18)	C57—C58—C59—C54	0.3 (3)
C51—C5—C6—O61	2.3 (2)	C57—C58—C59—S51	179.63 (13)
C4—C5—C6—O61	174.68 (15)	N53—C54—C59—C58	179.29 (14)
C51—C5—C6—O1	−174.44 (13)	C55—C54—C59—C58	0.5 (3)
C4—C5—C6—O1	−2.1 (2)	N53—C54—C59—S51	−0.18 (18)
C6—C5—C51—N51	−4.4 (3)	C55—C54—C59—S51	−178.92 (13)
C4—C5—C51—N51	−177.04 (15)	C52—S51—C59—C58	−179.69 (16)
C5—C51—N51—C52	177.55 (15)	C52—S51—C59—C54	−0.27 (12)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N51—H51···O61^i	0.88	2.23	3.028 (2)	151
N51—H51···O61	0.88	2.22	2.807 (2)	124

Symmetry code: (i) −x+2, −y+1, −z+2.