Methyl 2,2,4,8-tetra­methyl-6-oxo-2H,6H-pyrimidino­[2,1-b]­thia­zine-7-carboxyl­ate

The title compound, C₁₃H₁₆N₂O₃S, contains a non-planar thia­zine ring fused to a planar pyrimidine ring.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.045
• wR factor = 0.102
• Data-to-parameter ratio = 23.8

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

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Computing details

Data collection: CAD-4-PC (Enraf-Nonius, 1993) and EXPOSE (Stoe & Cie, 1997); cell refinement: CELDIM (Enraf-Nonius, 1993); data reduction: JANA2000 (Petricek and Dusek, 2000); program(s) used to solve structure: SHELXTL V5.0 (Sheldrick, 1995); program(s) used to refine structure: JANA2000 (Petricek and Dusek, 2000); molecular graphics: DIAMOND (Brandenburg & Berndt,1999); software used to prepare material for publication: JANA2000 (Petricek and Dusek, 2000).

Methyl 2,2,4,8-tetramethyl-6-oxo-2H,6H-pyrimidino[2,1-b]thiazine-7-carboxylate

Crystal data

C13H16N2O3S	F(000) = 592
Mr = 280.3	cell obtained from CAD4 reflection positions
Monoclinic, P21/c	Dx = 1.313 Mg m^−3
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71069 Å
a = 12.399 (5) Å	Cell parameters from 25 reflections
b = 12.8080 (9) Å	θ = 9.2–16.8°
c = 13.348 (5) Å	µ = 0.23 mm^−1
β = 138.032 (18)°	T = 293 K
V = 1417.5 (9) Å^3	Block, colourless
Z = 4	0.30 × 0.15 × 0.15 mm

Data collection

Nonius CAD-4 and Stoe IPDS diffractometer	4119 independent reflections
Radiation source: X-ray tube	2258 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.079
θ/2θ and ω scans	θmax = 30.1°, θmin = 2.3°
Absorption correction: gaussian (JANA2000; Petricek & Dusek, 2000)	h = −17→16
Tmin = 0.941, Tmax = 0.966	k = −17→17
28762 measured reflections	l = −17→18

Refinement

Refinement on F^2	Weighting scheme based on measured s.u.'s w = 1/[σ^2(I) + 0.0016I^2]
R[F > 3σ(F)] = 0.045	(Δ/σ)max = 0.0003
wR(F) = 0.102	Δρmax = 0.49 e Å^−3
S = 1.07	Δρmin = −0.42 e Å^−3
4119 reflections	Extinction correction: B-C type 1 Lorentzian isotropic (Becker & Coppens, 1974)
173 parameters	Extinction coefficient: 0.23 (4)
H-atom parameters not refined

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

	x	y	z	Uiso*/Ueq
S1	0.35400 (6)	0.38700 (4)	0.29114 (6)	0.0475 (4)
C2	0.1831 (2)	0.32248 (14)	0.2350 (2)	0.0445 (16)
C3	0.1777 (2)	0.36357 (14)	0.3363 (2)	0.0438 (15)
C4	0.2020 (2)	0.46106 (14)	0.38081 (19)	0.0408 (14)
N5	0.24172 (16)	0.53985 (11)	0.33462 (15)	0.0374 (11)
C6	0.1969 (2)	0.64582 (14)	0.3202 (2)	0.0443 (15)
C7	0.2803 (2)	0.72029 (14)	0.31621 (19)	0.0430 (14)
C8	0.3694 (2)	0.68783 (14)	0.29839 (19)	0.0432 (14)
N9	0.38510 (17)	0.58457 (12)	0.28621 (16)	0.0441 (13)
C9a	0.32388 (19)	0.51579 (13)	0.30467 (18)	0.0380 (13)
O1	0.3063 (2)	0.85653 (11)	0.44754 (17)	0.0731 (17)
O2	0.2034 (3)	0.89552 (14)	0.2301 (2)	0.119 (3)
O3	0.09226 (18)	0.66683 (11)	0.30885 (19)	0.0683 (17)
C10	0.2249 (3)	0.20678 (16)	0.2612 (3)	0.065 (2)
C11	0.0265 (3)	0.34370 (19)	0.0717 (2)	0.0676 (18)
C12	0.2082 (3)	0.49399 (17)	0.4933 (2)	0.059 (2)
C13	0.4528 (3)	0.75958 (17)	0.2838 (2)	0.061 (2)
C14	0.2563 (3)	0.83258 (16)	0.3229 (2)	0.056 (2)
C15	0.2930 (4)	0.96485 (18)	0.4683 (3)	0.087 (3)
H3	0.1545	0.3213	0.3793	0.054*
H10a	0.1374	0.1673	0.2323	0.082*
H10b	0.326	0.1934	0.3668	0.082*
H10c	0.2362	0.1848	0.199	0.082*
H11a	0.0347	0.3199	0.0078	0.085*
H11b	0.0069	0.4192	0.0593	0.085*
H11c	−0.063	0.3077	0.0431	0.085*
H12a	0.2141	0.4293	0.5365	0.074*
H12b	0.1105	0.5325	0.4443	0.074*
H12c	0.3033	0.537	0.5731	0.074*
H13a	0.3902	0.7613	0.1783	0.075*
H13b	0.5601	0.7308	0.3445	0.075*
H13c	0.4635	0.8306	0.3177	0.075*
H15a	0.3686	1.0026	0.4773	0.109*
H15b	0.3268	0.9716	0.5617	0.109*
H15c	0.1845	0.994	0.3852	0.109*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0526 (3)	0.0407 (3)	0.0635 (3)	−0.0019 (2)	0.0475 (3)	−0.0057 (2)
C2	0.0451 (10)	0.0383 (10)	0.0468 (10)	−0.0062 (7)	0.0332 (10)	−0.0053 (8)
C3	0.0465 (10)	0.0434 (11)	0.0488 (10)	−0.0030 (8)	0.0376 (9)	0.0022 (8)
C4	0.0407 (9)	0.0425 (10)	0.0429 (9)	−0.0017 (8)	0.0322 (8)	0.0014 (8)
N5	0.0392 (7)	0.0363 (8)	0.0415 (7)	−0.0013 (6)	0.0314 (7)	−0.0004 (6)
C6	0.0465 (10)	0.0402 (10)	0.0494 (10)	0.0031 (8)	0.0366 (9)	0.0011 (8)
C7	0.0477 (10)	0.0380 (10)	0.0393 (9)	0.0008 (8)	0.0312 (9)	0.0037 (8)
C8	0.0446 (10)	0.0413 (10)	0.0388 (9)	−0.0045 (8)	0.0296 (9)	0.0002 (8)
N9	0.0473 (9)	0.0445 (9)	0.0496 (9)	−0.0045 (7)	0.0387 (8)	−0.0019 (7)
C9a	0.0366 (8)	0.0406 (10)	0.0371 (9)	−0.0018 (7)	0.0275 (8)	−0.0016 (7)
O1	0.1184 (13)	0.0385 (8)	0.0702 (10)	0.0015 (8)	0.0725 (10)	0.0000 (7)
O2	0.218 (2)	0.0652 (12)	0.1143 (15)	0.0545 (14)	0.1357 (18)	0.0432 (11)
O3	0.0783 (10)	0.0493 (9)	0.1122 (12)	0.0105 (7)	0.0813 (11)	0.0075 (8)
C10	0.0815 (15)	0.0424 (12)	0.0885 (16)	−0.0082 (11)	0.0683 (14)	−0.0088 (11)
C11	0.0554 (12)	0.0803 (17)	0.0469 (12)	−0.0113 (11)	0.0320 (11)	−0.0079 (11)
C12	0.0796 (14)	0.0560 (13)	0.0702 (13)	−0.0028 (11)	0.0646 (13)	−0.0015 (10)
C13	0.0716 (13)	0.0517 (13)	0.0729 (13)	−0.0091 (10)	0.0579 (12)	0.0027 (11)
C14	0.0750 (14)	0.0432 (11)	0.0602 (13)	0.0078 (10)	0.0534 (12)	0.0111 (10)
C15	0.141 (2)	0.0410 (13)	0.111 (2)	−0.0055 (14)	0.103 (2)	−0.0114 (13)

Geometric parameters (Å, º)

S1—C2	1.837 (3)	O1—C14	1.308 (4)
S1—C9a	1.7303 (17)	O1—C15	1.448 (3)
C2—C3	1.498 (4)	O2—C14	1.186 (3)
C2—C10	1.522 (3)	C10—H10a	0.98
C2—C11	1.517 (2)	C10—H10b	0.98
C3—C4	1.318 (2)	C10—H10c	0.98
C3—H3	0.98	C11—H11a	0.98
C4—N5	1.446 (3)	C11—H11b	0.98
C4—C12	1.506 (5)	C11—H11c	0.98
N5—C6	1.425 (2)	C12—H12a	0.98
N5—C9a	1.378 (4)	C12—H12b	0.98
C6—C7	1.437 (4)	C12—H12c	0.98
C6—O3	1.218 (4)	C13—H13a	0.98
C7—C8	1.357 (5)	C13—H13b	0.98
C7—C14	1.485 (3)	C13—H13c	0.98
C8—N9	1.363 (2)	C15—H15a	0.98
C8—C13	1.501 (5)	C15—H15b	0.98
N9—C9a	1.301 (4)	C15—H15c	0.98
C2—S1—C9a	101.44 (11)	C2—C10—H10c	108.9
S1—C2—C3	106.62 (11)	H10a—C10—H10b	109.5
S1—C2—C10	104.6 (2)	H10a—C10—H10c	109.4
S1—C2—C11	111.2 (2)	H10b—C10—H10c	109.4
C3—C2—C10	111.8 (2)	C2—C11—H11a	110.2
C3—C2—C11	111.4 (2)	C2—C11—H11b	108.1
C10—C2—C11	110.96 (16)	C2—C11—H11c	110.2
C2—C3—C4	126.2 (3)	H11a—C11—H11b	109.4
C2—C3—H3	124.5	H11a—C11—H11c	109.5
C4—C3—H3	109.3	H11b—C11—H11c	109.4
C3—C4—N5	120.3 (3)	C4—C12—H12a	106.0
C3—C4—C12	122.7 (3)	C4—C12—H12b	110.7
N5—C4—C12	116.69 (16)	C4—C12—H12c	111.6
C4—N5—C6	120.0 (2)	H12a—C12—H12b	109.4
C4—N5—C9a	121.87 (16)	H12a—C12—H12c	109.4
C6—N5—C9a	118.2 (2)	H12b—C12—H12c	109.5
N5—C6—C7	114.7 (2)	C8—C13—H13a	108.3
N5—C6—O3	120.0 (2)	C8—C13—H13b	107.8
C7—C6—O3	125.27 (15)	C8—C13—H13c	112.3
C6—C7—C8	120.33 (15)	H13a—C13—H13b	109.5
C6—C7—C14	117.3 (3)	H13a—C13—H13c	109.5
C8—C7—C14	122.2 (2)	H13b—C13—H13c	109.5
C7—C8—N9	121.7 (2)	C7—C14—O1	112.1 (2)
C7—C8—C13	124.34 (17)	C7—C14—O2	125.1 (3)
N9—C8—C13	113.9 (3)	O1—C14—O2	122.7 (3)
C8—N9—C9a	118.6 (3)	O1—C15—H15a	105.2
S1—C9a—N5	120.44 (16)	O1—C15—H15b	109.1
S1—C9a—N9	115.1 (2)	O1—C15—H15c	113.9
N5—C9a—N9	124.44 (17)	H15a—C15—H15b	109.5
C14—O1—C15	117.0 (2)	H15a—C15—H15c	109.5
C2—C10—H10a	108.9	H15b—C15—H15c	109.5
C2—C10—H10b	110.8