(4S,5S)-2-Benzyl­oxy-4-methyl-5-(4-tolyl­thio­carbonyl)­oxazoline

The five-membered ring in the title compound, C₁₉H₁₉NO₃S, is almost planar. The cis configuration of the ring substituents and the absolute configuration determination confirm the proposed mechanism of the stereospecific synthesis.

Key indicators

• Single-crystal X-ray study
• T = 160 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.030
• wR factor = 0.079
• Data-to-parameter ratio = 15.4

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level C:



ABSTM_02  Alert C The ratio of expected to reported Tmax/Tmin(RR') is < 0.90
          Tmin and Tmax reported:      0.750     0.928
          Tmin' and Tmax expected:      0.901     0.936
          RR' =      0.839
          Please check that your absorption correction is appropriate.

General Notes



REFLT_03
         From the CIF: _diffrn_reflns_theta_max           28.70
         From the CIF: _reflns_number_total               3382
         Count of symmetry unique reflns         2536
         Completeness (_total/calc)            133.36%
         TEST3: Check Friedels for noncentro structure
         Estimate of Friedel pairs measured       846
         Fraction of Friedel pairs measured     0.334
         Are heavy atom types Z>Si present          yes
          WARNING: Large fraction of Friedel related reflns may
                   be needed to determine absolute structure


 0 Alert Level A = Potentially serious problem

 0 Alert Level B = Potential problem

 1 Alert Level C = Please check

---

Computing details

Data collection: SMART (Siemens, 1995); cell refinement: local programs; data reduction: SAINT (Siemens, 1995); program(s) used to solve structure: SHELXTL (Sheldrick, 1994); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and local programs.

(4S,5S)-2-Benzyloxy-4-methyl-5-(4-tolylthiocarbonyl)oxazoline

Crystal data

C19H19NO3S	F(000) = 360
Mr = 341.41	Dx = 1.266 Mg m^−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
a = 11.9010 (9) Å	Cell parameters from 6005 reflections
b = 5.7705 (4) Å	θ = 2.7–28.7°
c = 13.7964 (10) Å	µ = 0.20 mm^−1
β = 109.043 (2)°	T = 160 K
V = 895.61 (11) Å^3	Rectangular block, colourless
Z = 2	0.52 × 0.40 × 0.34 mm

Data collection

Siemens SMART 1K CCD diffractometer	3382 independent reflections
Radiation source: sealed tube	3203 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.018
Detector resolution: 8.192 pixels mm^-1	θmax = 28.7°, θmin = 1.8°
ω rotation with narrow frames scans	h = −15→15
Absorption correction: multi-scan (XPREP in SHELXTL; Sheldrick, 1994)	k = −6→7
Tmin = 0.750, Tmax = 0.928	l = −17→18
6725 measured reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.030	H-atom parameters constrained
wR(F^2) = 0.079	w = 1/[σ^2(Fo^2) + (0.0493P)^2 + 0.0826P] where P = (Fo^2 + 2Fc^2)/3
S = 1.03	(Δ/σ)max < 0.001
3382 reflections	Δρmax = 0.21 e Å^−3
219 parameters	Δρmin = −0.19 e Å^−3
1 restraint	Absolute structure: Flack (1983), 1056 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.08 (6)

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

	x	y	z	Uiso*/Ueq
O1	0.77056 (9)	0.15718 (19)	0.88474 (9)	0.0315 (3)
C1	0.80856 (12)	0.3805 (3)	0.90228 (10)	0.0250 (3)
N1	0.75829 (11)	0.5210 (2)	0.94457 (9)	0.0281 (3)
C2	0.66024 (12)	0.3912 (3)	0.96289 (10)	0.0257 (3)
H2	0.6778	0.3730	1.0385	0.031*
C3	0.66524 (12)	0.1468 (3)	0.91457 (11)	0.0263 (3)
H3	0.6751	0.0242	0.9679	0.032*
C4	0.55805 (12)	0.0917 (3)	0.82225 (10)	0.0251 (3)
O2	0.46249 (9)	0.0483 (2)	0.83037 (8)	0.0302 (2)
C5	0.54399 (14)	0.5225 (3)	0.91859 (12)	0.0322 (3)
H5A	0.5506	0.6741	0.9520	0.048*
H5B	0.4794	0.4339	0.9305	0.048*
H5C	0.5270	0.5441	0.8447	0.048*
O3	0.90081 (9)	0.4140 (2)	0.86971 (8)	0.0291 (2)
C6	0.95440 (14)	0.6417 (3)	0.89320 (13)	0.0330 (3)
H6A	0.9910	0.6609	0.9683	0.040*
H6B	0.8935	0.7637	0.8673	0.040*
C7	1.04768 (13)	0.6597 (3)	0.84150 (11)	0.0269 (3)
C8	1.12865 (13)	0.4826 (3)	0.84919 (11)	0.0290 (3)
H8	1.1265	0.3482	0.8883	0.035*
C9	1.21306 (14)	0.5010 (3)	0.79981 (12)	0.0341 (4)
H9	1.2676	0.3781	0.8040	0.041*
C10	1.21756 (15)	0.7000 (4)	0.74417 (13)	0.0385 (4)
H10	1.2753	0.7133	0.7105	0.046*
C11	1.13857 (17)	0.8765 (4)	0.73799 (13)	0.0416 (4)
H11	1.1424	1.0130	0.7007	0.050*
C12	1.05275 (15)	0.8572 (3)	0.78591 (13)	0.0357 (4)
H12	0.9976	0.9794	0.7805	0.043*
S1	0.58788 (4)	0.10061 (8)	0.70389 (3)	0.03961 (12)
C13	0.44347 (16)	0.0351 (3)	0.61861 (12)	0.0352 (4)
C14	0.42437 (18)	−0.1741 (4)	0.56673 (13)	0.0411 (4)
H14	0.4875	−0.2821	0.5772	0.049*
C15	0.3119 (2)	−0.2245 (4)	0.49909 (13)	0.0472 (5)
H15	0.2988	−0.3679	0.4633	0.057*
C16	0.2187 (2)	−0.0705 (4)	0.48289 (13)	0.0482 (5)
C17	0.23960 (19)	0.1389 (4)	0.53491 (13)	0.0484 (5)
H17	0.1765	0.2470	0.5242	0.058*
C18	0.35148 (17)	0.1930 (3)	0.60242 (13)	0.0413 (4)
H18	0.3649	0.3375	0.6373	0.050*
C19	0.0957 (2)	−0.1310 (6)	0.41158 (18)	0.0787 (9)
H19A	0.0615	−0.2533	0.4426	0.118*
H19B	0.1011	−0.1857	0.3460	0.118*
H19C	0.0449	0.0068	0.4000	0.118*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0203 (5)	0.0217 (6)	0.0542 (6)	−0.0026 (4)	0.0147 (5)	−0.0020 (5)
C1	0.0183 (6)	0.0241 (7)	0.0298 (7)	−0.0029 (6)	0.0039 (5)	0.0012 (6)
N1	0.0252 (6)	0.0276 (7)	0.0327 (6)	−0.0077 (6)	0.0111 (5)	−0.0042 (5)
C2	0.0243 (7)	0.0251 (8)	0.0282 (6)	−0.0056 (6)	0.0093 (6)	0.0000 (6)
C3	0.0198 (6)	0.0237 (8)	0.0358 (7)	−0.0032 (6)	0.0096 (5)	0.0038 (6)
C4	0.0246 (7)	0.0202 (7)	0.0316 (6)	−0.0026 (6)	0.0108 (5)	0.0015 (6)
O2	0.0217 (5)	0.0374 (7)	0.0321 (5)	−0.0073 (5)	0.0095 (4)	0.0017 (4)
C5	0.0299 (8)	0.0275 (8)	0.0436 (8)	0.0004 (7)	0.0181 (7)	0.0010 (7)
O3	0.0200 (5)	0.0250 (6)	0.0444 (6)	−0.0055 (4)	0.0133 (4)	−0.0044 (5)
C6	0.0303 (8)	0.0259 (9)	0.0473 (8)	−0.0099 (7)	0.0187 (7)	−0.0096 (7)
C7	0.0210 (7)	0.0276 (8)	0.0311 (6)	−0.0073 (6)	0.0070 (5)	−0.0059 (6)
C8	0.0246 (7)	0.0292 (8)	0.0308 (7)	−0.0045 (6)	0.0057 (6)	−0.0003 (6)
C9	0.0212 (7)	0.0413 (10)	0.0382 (8)	−0.0029 (7)	0.0074 (6)	−0.0068 (7)
C10	0.0347 (9)	0.0465 (11)	0.0397 (8)	−0.0140 (8)	0.0196 (7)	−0.0075 (7)
C11	0.0511 (11)	0.0361 (10)	0.0418 (9)	−0.0114 (9)	0.0211 (8)	0.0037 (8)
C12	0.0352 (9)	0.0284 (9)	0.0436 (8)	−0.0018 (7)	0.0128 (7)	0.0009 (7)
S1	0.0357 (2)	0.0519 (3)	0.0380 (2)	−0.0130 (2)	0.02127 (17)	−0.00887 (18)
C13	0.0423 (9)	0.0396 (10)	0.0272 (7)	−0.0107 (8)	0.0161 (6)	−0.0032 (6)
C14	0.0535 (11)	0.0428 (11)	0.0334 (8)	−0.0082 (9)	0.0229 (8)	−0.0067 (7)
C15	0.0709 (13)	0.0446 (11)	0.0270 (7)	−0.0200 (11)	0.0170 (8)	−0.0075 (7)
C16	0.0576 (12)	0.0519 (12)	0.0263 (8)	−0.0164 (11)	0.0018 (8)	0.0079 (7)
C17	0.0514 (11)	0.0458 (12)	0.0389 (8)	−0.0018 (10)	0.0024 (8)	0.0104 (8)
C18	0.0510 (11)	0.0360 (10)	0.0351 (8)	−0.0080 (9)	0.0118 (8)	−0.0006 (7)
C19	0.0755 (17)	0.082 (2)	0.0489 (12)	−0.0262 (16)	−0.0202 (11)	0.0105 (12)

Geometric parameters (Å, º)

O1—C1	1.361 (2)	C9—H9	0.950
O1—C3	1.4424 (16)	C9—C10	1.392 (3)
C1—N1	1.258 (2)	C10—H10	0.950
C1—O3	1.3292 (17)	C10—C11	1.370 (3)
N1—C2	1.4760 (19)	C11—H11	0.950
C2—H2	1.000	C11—C12	1.390 (2)
C2—C3	1.569 (2)	C12—H12	0.950
C2—C5	1.520 (2)	S1—C13	1.7781 (18)
C3—H3	1.000	C13—C14	1.384 (3)
C3—C4	1.513 (2)	C13—C18	1.385 (3)
C4—O2	1.2048 (16)	C14—H14	0.950
C4—S1	1.7815 (13)	C14—C15	1.390 (3)
C5—H5A	0.980	C15—H15	0.950
C5—H5B	0.980	C15—C16	1.382 (3)
C5—H5C	0.980	C16—C17	1.386 (3)
O3—C6	1.4501 (19)	C16—C19	1.514 (3)
C6—H6A	0.990	C17—H17	0.950
C6—H6B	0.990	C17—C18	1.389 (3)
C6—C7	1.5061 (19)	C18—H18	0.950
C7—C8	1.385 (2)	C19—H19A	0.980
C7—C12	1.386 (2)	C19—H19B	0.980
C8—H8	0.950	C19—H19C	0.980
C8—C9	1.390 (2)
C1—O1—C3	104.94 (11)	H8—C8—C9	119.9
O1—C1—N1	120.79 (13)	C8—C9—H9	120.1
O1—C1—O3	109.94 (13)	C8—C9—C10	119.84 (16)
N1—C1—O3	129.27 (15)	H9—C9—C10	120.1
C1—N1—C2	105.93 (14)	C9—C10—H10	120.0
N1—C2—H2	108.9	C9—C10—C11	119.91 (15)
N1—C2—C3	103.97 (11)	H10—C10—C11	120.0
N1—C2—C5	110.19 (13)	C10—C11—H11	119.8
H2—C2—C3	108.9	C10—C11—C12	120.43 (17)
H2—C2—C5	108.9	H11—C11—C12	119.8
C3—C2—C5	115.65 (13)	C7—C12—C11	120.02 (16)
O1—C3—C2	103.94 (11)	C7—C12—H12	120.0
O1—C3—H3	109.6	C11—C12—H12	120.0
O1—C3—C4	109.94 (11)	C4—S1—C13	99.31 (7)
C2—C3—H3	109.6	S1—C13—C14	119.21 (15)
C2—C3—C4	114.07 (13)	S1—C13—C18	120.61 (14)
H3—C3—C4	109.6	C14—C13—C18	120.16 (17)
C3—C4—O2	121.84 (12)	C13—C14—H14	120.3
C3—C4—S1	113.58 (9)	C13—C14—C15	119.3 (2)
O2—C4—S1	124.58 (11)	H14—C14—C15	120.3
C2—C5—H5A	109.5	C14—C15—H15	119.3
C2—C5—H5B	109.5	C14—C15—C16	121.35 (18)
C2—C5—H5C	109.5	H15—C15—C16	119.3
H5A—C5—H5B	109.5	C15—C16—C17	118.56 (18)
H5A—C5—H5C	109.5	C15—C16—C19	120.8 (2)
H5B—C5—H5C	109.5	C17—C16—C19	120.7 (2)
C1—O3—C6	114.08 (12)	C16—C17—H17	119.5
O3—C6—H6A	110.3	C16—C17—C18	120.9 (2)
O3—C6—H6B	110.3	H17—C17—C18	119.5
O3—C6—C7	107.15 (12)	C13—C18—C17	119.66 (18)
H6A—C6—H6B	108.5	C13—C18—H18	120.2
H6A—C6—C7	110.3	C17—C18—H18	120.2
H6B—C6—C7	110.3	C16—C19—H19A	109.5
C6—C7—C8	121.00 (14)	C16—C19—H19B	109.5
C6—C7—C12	119.38 (14)	C16—C19—H19C	109.5
C8—C7—C12	119.62 (14)	H19A—C19—H19B	109.5
C7—C8—H8	119.9	H19A—C19—H19C	109.5
C7—C8—C9	120.16 (15)	H19B—C19—H19C	109.5
C3—O1—C1—N1	5.39 (18)	C12—C7—C8—C9	−1.2 (2)
C3—O1—C1—O3	−175.19 (11)	C7—C8—C9—C10	1.3 (2)
O1—C1—N1—C2	−1.42 (18)	C8—C9—C10—C11	−0.2 (2)
O3—C1—N1—C2	179.28 (14)	C9—C10—C11—C12	−0.8 (3)
C1—N1—C2—C3	−2.87 (15)	C6—C7—C12—C11	179.83 (15)
C1—N1—C2—C5	−127.40 (14)	C8—C7—C12—C11	0.2 (2)
C1—O1—C3—C2	−6.31 (14)	C10—C11—C12—C7	0.8 (3)
C1—O1—C3—C4	116.17 (13)	C3—C4—S1—C13	−178.74 (12)
N1—C2—C3—O1	5.71 (14)	O2—C4—S1—C13	0.73 (17)
N1—C2—C3—C4	−114.00 (13)	C4—S1—C13—C14	−111.95 (13)
C5—C2—C3—O1	126.64 (12)	C4—S1—C13—C18	69.38 (14)
C5—C2—C3—C4	6.93 (17)	S1—C13—C14—C15	−179.25 (13)
O1—C3—C4—O2	171.41 (14)	C18—C13—C14—C15	−0.6 (2)
O1—C3—C4—S1	−9.11 (16)	C13—C14—C15—C16	−0.2 (2)
C2—C3—C4—O2	−72.31 (19)	C14—C15—C16—C17	0.7 (3)
C2—C3—C4—S1	107.17 (12)	C14—C15—C16—C19	−178.03 (18)
O1—C1—O3—C6	−174.87 (12)	C15—C16—C17—C18	−0.4 (3)
N1—C1—O3—C6	4.5 (2)	C19—C16—C17—C18	178.34 (18)
C1—O3—C6—C7	−173.95 (12)	S1—C13—C18—C17	179.53 (13)
O3—C6—C7—C8	−46.97 (18)	C14—C13—C18—C17	0.9 (2)
O3—C6—C7—C12	133.39 (15)	C16—C17—C18—C13	−0.4 (3)
C6—C7—C8—C9	179.14 (14)