organic compounds
S-Phenethyl (2R,3R)-3-{[(R)-tert-butylsulfinyl]amino}-2-fluoro-3-phenylpropanethioate
aDepartment of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai, People's Republic of China
*Correspondence e-mail: ya.li@sues.edu.cn
The title compound, C21H26FNO2S2, contains two chiral carbon centres and the has been confirmed as (2R,3R). The dihedral angle between the phenyl rings is 87.1 (2) and the O—C—C—F and F—C—C—N torsion angles are −175.4 (4) and 62.7 (4)°, respectively. In the crystal, N—H⋯O hydrogen bonds link the molecules into C(4) [010] chains and weak C—H⋯O and C—H⋯F interactions cross-link the chains, generating a three-dimensional network.
Keywords: crystal structure; amine; fluorine; thioester; chiral carbon..
CCDC reference: 1837176
Structure description
A chiral carbon atom bearing a fluorine substituent is an important structural motif in many bioactive molecules (Wang et al., 2014; Purser et al., 2008). Not surprisingly, the synthesis of chiral molecules with a fluorinated carbon center has attracted recent attention (Shang et al., 2015; Chen et al., 2017). As part of our work in this area, we now describe the synthesis and structure of the title compound (Fig. 1).
The fluoro and amino substituents adopt a gauche conformation [F1—C2—C3—N1 = 62.7 (4)°] and the of the chiral carbon centres, C2 and C3, has been confirmed as (R,R). In the crystal, molecules are connected by N—H⋯O hydrogen bonds (Table 1, Fig. 2), generating C(4) [010] chains, with adjacent molecules related by the 21 screw axis. Weak C—H⋯O and C—H⋯F interactions cross-link the chains to generate a three-dimensional network.
Synthesis and crystallization
Potassium bis(trimethylsilyl)amide (1.2 mmol, 1M in toluene) was added slowly to a reaction mixture of (R)-N-benzylidene- 2-methylpropane-2-sulfinamide (209 mg, 1.0 mmol) and S-phenethyl 2-fluoroethanethioate (198 mg, 1.0 mmol) in toluene at 213 K. The reaction mixture was stirred for 1 h at this temperature and then quenched with saturated NH4Cl/H2O. The quenched mixture was extracted with EtOAc (20 ml × 3) and the combined organic layers were dried with Na2SO4. After removal of the solvent under reduced pressure, the residue was subjected to flash to give the title compound (253 mg: yield, 62%). The obtained compound was recrystallized from mixed solvents of ethyl acetate/n-hexane (1:2) to give colorless prisms.
Refinement
Crystal data, data collection and structure .
details are summarized in Table 2Structural data
CCDC reference: 1837176
https://doi.org/10.1107/S2414314618005862/hb4225sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314618005862/hb4225Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2414314618005862/hb4225Isup3.cml
Data collection: SMART (Bruker, 2007); cell
SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2015); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).C21H26FNO2S2 | F(000) = 432 |
Mr = 407.55 | Dx = 1.253 Mg m−3 |
Monoclinic, P21 | Mo Kα radiation, λ = 0.71073 Å |
a = 13.282 (2) Å | Cell parameters from 2551 reflections |
b = 5.8005 (9) Å | θ = 5.8–51.0° |
c = 14.622 (2) Å | µ = 0.27 mm−1 |
β = 106.418 (3)° | T = 293 K |
V = 1080.6 (3) Å3 | Prism, colorless |
Z = 2 | 0.20 × 0.16 × 0.13 mm |
Bruker SMART CCD diffractometer | 3464 reflections with I > 2σ(I) |
phi and ω scans | Rint = 0.023 |
Absorption correction: multi-scan (SADABS; Bruker, 2007) | θmax = 25.5°, θmin = 1.5° |
Tmin = 0.641, Tmax = 0.746 | h = −15→16 |
6235 measured reflections | k = −7→6 |
3783 independent reflections | l = −17→15 |
Refinement on F2 | Hydrogen site location: mixed |
Least-squares matrix: full | H atoms treated by a mixture of independent and constrained refinement |
R[F2 > 2σ(F2)] = 0.047 | w = 1/[σ2(Fo2) + (0.070P)2 + 0.1132P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.121 | (Δ/σ)max = 0.001 |
S = 1.07 | Δρmax = 0.42 e Å−3 |
3783 reflections | Δρmin = −0.20 e Å−3 |
239 parameters | Absolute structure: Flack x determined using 1338 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013) |
2 restraints | Absolute structure parameter: 0.04 (5) |
Primary atom site location: structure-invariant direct methods |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
S1 | 0.11978 (11) | 0.2731 (3) | 0.64914 (8) | 0.0787 (5) | |
S2 | 0.17919 (6) | −0.19558 (15) | 1.06022 (6) | 0.0398 (2) | |
F1 | 0.12082 (17) | 0.3427 (4) | 0.83432 (15) | 0.0532 (6) | |
N1 | 0.1447 (2) | 0.0152 (5) | 0.9803 (2) | 0.0408 (7) | |
O1 | 0.0356 (3) | −0.1192 (8) | 0.6793 (2) | 0.0896 (13) | |
O2 | 0.0869 (2) | −0.3401 (5) | 1.06159 (19) | 0.0532 (7) | |
C1 | 0.0733 (3) | 0.0590 (9) | 0.7120 (3) | 0.0539 (11) | |
C2 | 0.0821 (3) | 0.1211 (7) | 0.8147 (3) | 0.0445 (9) | |
H2 | 0.0116 | 0.1165 | 0.8233 | 0.053* | |
C3 | 0.1505 (3) | −0.0470 (7) | 0.8839 (2) | 0.0392 (8) | |
H3 | 0.1210 | −0.2019 | 0.8688 | 0.047* | |
C4 | 0.2636 (3) | −0.0500 (7) | 0.8796 (2) | 0.0411 (8) | |
C5 | 0.2989 (3) | −0.2268 (8) | 0.8348 (3) | 0.0541 (10) | |
H5 | 0.2540 | −0.3479 | 0.8088 | 0.065* | |
C6 | 0.4009 (4) | −0.2276 (10) | 0.8276 (3) | 0.0693 (14) | |
H6 | 0.4242 | −0.3492 | 0.7974 | 0.083* | |
C7 | 0.4669 (4) | −0.0499 (11) | 0.8648 (3) | 0.0666 (13) | |
H7 | 0.5352 | −0.0504 | 0.8600 | 0.080* | |
C8 | 0.4333 (3) | 0.1275 (10) | 0.9090 (3) | 0.0611 (12) | |
H8 | 0.4786 | 0.2487 | 0.9339 | 0.073* | |
C9 | 0.3317 (3) | 0.1294 (8) | 0.9172 (3) | 0.0484 (9) | |
H9 | 0.3093 | 0.2511 | 0.9480 | 0.058* | |
C10 | 0.0993 (5) | 0.1323 (18) | 0.5367 (3) | 0.108 (3) | |
H10A | 0.0431 | 0.0209 | 0.5290 | 0.129* | |
H10B | 0.0769 | 0.2459 | 0.4863 | 0.129* | |
C11 | 0.1951 (6) | 0.0108 (14) | 0.5253 (4) | 0.099 (2) | |
H11A | 0.2147 | −0.1100 | 0.5729 | 0.119* | |
H11B | 0.1778 | −0.0618 | 0.4630 | 0.119* | |
C12 | 0.2864 (3) | 0.1658 (7) | 0.5349 (3) | 0.0712 (13) | |
C13 | 0.3702 (3) | 0.1569 (8) | 0.6172 (2) | 0.096 (2) | |
H13 | 0.3716 | 0.0453 | 0.6633 | 0.116* | |
C14 | 0.4518 (3) | 0.3147 (10) | 0.6308 (3) | 0.113 (2) | |
H14 | 0.5079 | 0.3086 | 0.6859 | 0.135* | |
C15 | 0.4497 (3) | 0.4814 (9) | 0.5620 (4) | 0.111 (2) | |
H15 | 0.5043 | 0.5870 | 0.5711 | 0.134* | |
C16 | 0.3659 (4) | 0.4904 (8) | 0.4797 (3) | 0.115 (2) | |
H16 | 0.3645 | 0.6020 | 0.4337 | 0.138* | |
C17 | 0.2843 (3) | 0.3326 (8) | 0.4662 (2) | 0.0908 (18) | |
H17 | 0.2282 | 0.3386 | 0.4111 | 0.109* | |
C18 | 0.2062 (3) | −0.0176 (7) | 1.1688 (3) | 0.0450 (9) | |
C19 | 0.3005 (4) | 0.1355 (11) | 1.1702 (4) | 0.0706 (13) | |
H19A | 0.3246 | 0.2109 | 1.2309 | 0.106* | |
H19B | 0.2801 | 0.2493 | 1.1207 | 0.106* | |
H19C | 0.3560 | 0.0424 | 1.1597 | 0.106* | |
C20 | 0.2345 (3) | −0.1915 (11) | 1.2502 (3) | 0.0635 (11) | |
H20A | 0.2546 | −0.1112 | 1.3100 | 0.095* | |
H20B | 0.2920 | −0.2853 | 1.2444 | 0.095* | |
H20C | 0.1749 | −0.2877 | 1.2474 | 0.095* | |
C21 | 0.1111 (3) | 0.1219 (8) | 1.1702 (3) | 0.0541 (10) | |
H21A | 0.0504 | 0.0241 | 1.1549 | 0.081* | |
H21B | 0.1014 | 0.2435 | 1.1240 | 0.081* | |
H21C | 0.1211 | 0.1870 | 1.2324 | 0.081* | |
H1 | 0.091 (2) | 0.077 (6) | 0.981 (2) | 0.031 (10)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.0949 (9) | 0.0960 (12) | 0.0526 (6) | −0.0127 (8) | 0.0327 (6) | 0.0105 (7) |
S2 | 0.0388 (4) | 0.0394 (5) | 0.0433 (4) | 0.0024 (4) | 0.0148 (3) | 0.0068 (4) |
F1 | 0.0646 (13) | 0.0437 (15) | 0.0552 (12) | 0.0092 (11) | 0.0232 (10) | 0.0062 (10) |
N1 | 0.0428 (17) | 0.0433 (18) | 0.0416 (16) | 0.0072 (14) | 0.0208 (13) | 0.0072 (14) |
O1 | 0.110 (3) | 0.101 (3) | 0.0525 (18) | −0.042 (2) | 0.0156 (17) | −0.0191 (19) |
O2 | 0.0562 (16) | 0.0516 (17) | 0.0524 (15) | −0.0134 (14) | 0.0161 (12) | 0.0060 (13) |
C1 | 0.042 (2) | 0.075 (3) | 0.042 (2) | −0.002 (2) | 0.0075 (16) | 0.002 (2) |
C2 | 0.0374 (18) | 0.053 (2) | 0.0455 (19) | 0.0031 (17) | 0.0153 (15) | 0.0010 (18) |
C3 | 0.0439 (19) | 0.038 (2) | 0.0407 (18) | −0.0002 (15) | 0.0194 (15) | 0.0000 (15) |
C4 | 0.0423 (19) | 0.043 (2) | 0.0397 (18) | 0.0060 (16) | 0.0144 (14) | 0.0072 (16) |
C5 | 0.063 (2) | 0.048 (3) | 0.056 (2) | 0.010 (2) | 0.0252 (18) | 0.001 (2) |
C6 | 0.075 (3) | 0.069 (3) | 0.076 (3) | 0.032 (3) | 0.041 (2) | 0.013 (3) |
C7 | 0.047 (2) | 0.090 (4) | 0.069 (3) | 0.022 (3) | 0.027 (2) | 0.021 (3) |
C8 | 0.043 (2) | 0.081 (3) | 0.059 (2) | −0.003 (2) | 0.0139 (18) | 0.011 (2) |
C9 | 0.046 (2) | 0.054 (2) | 0.049 (2) | 0.0002 (18) | 0.0198 (16) | 0.0007 (19) |
C10 | 0.094 (4) | 0.183 (8) | 0.046 (3) | −0.024 (5) | 0.020 (3) | 0.004 (4) |
C11 | 0.133 (5) | 0.102 (5) | 0.070 (3) | −0.008 (4) | 0.042 (3) | −0.019 (3) |
C12 | 0.083 (3) | 0.078 (4) | 0.061 (3) | 0.011 (3) | 0.033 (2) | −0.005 (3) |
C13 | 0.095 (4) | 0.127 (6) | 0.067 (3) | 0.030 (4) | 0.024 (3) | 0.026 (4) |
C14 | 0.084 (4) | 0.162 (7) | 0.089 (4) | 0.010 (6) | 0.020 (3) | 0.011 (6) |
C15 | 0.092 (5) | 0.126 (6) | 0.124 (6) | −0.009 (5) | 0.042 (4) | −0.003 (5) |
C16 | 0.119 (5) | 0.119 (6) | 0.111 (5) | 0.011 (5) | 0.041 (4) | 0.046 (5) |
C17 | 0.096 (4) | 0.112 (5) | 0.064 (3) | 0.009 (4) | 0.020 (2) | 0.017 (4) |
C18 | 0.0420 (19) | 0.050 (2) | 0.0416 (19) | −0.0077 (17) | 0.0099 (15) | 0.0011 (17) |
C19 | 0.056 (3) | 0.082 (4) | 0.070 (3) | −0.027 (3) | 0.012 (2) | −0.008 (3) |
C20 | 0.066 (2) | 0.073 (3) | 0.0447 (19) | 0.000 (3) | 0.0049 (16) | 0.012 (2) |
C21 | 0.062 (2) | 0.052 (2) | 0.053 (2) | 0.003 (2) | 0.0226 (18) | −0.003 (2) |
S1—C1 | 1.758 (5) | C10—H10B | 0.9700 |
S1—C10 | 1.787 (7) | C11—C12 | 1.484 (8) |
S2—O2 | 1.489 (3) | C11—H11A | 0.9700 |
S2—N1 | 1.664 (3) | C11—H11B | 0.9700 |
S2—C18 | 1.843 (4) | C12—C13 | 1.3900 |
F1—C2 | 1.384 (5) | C12—C17 | 1.3900 |
N1—C3 | 1.477 (4) | C13—C14 | 1.3900 |
N1—H1 | 0.80 (2) | C13—H13 | 0.9300 |
O1—C1 | 1.188 (6) | C14—C15 | 1.3900 |
C1—C2 | 1.516 (5) | C14—H14 | 0.9300 |
C2—C3 | 1.510 (5) | C15—C16 | 1.3900 |
C2—H2 | 0.9800 | C15—H15 | 0.9300 |
C3—C4 | 1.522 (5) | C16—C17 | 1.3900 |
C3—H3 | 0.9800 | C16—H16 | 0.9300 |
C4—C5 | 1.370 (6) | C17—H17 | 0.9300 |
C4—C9 | 1.387 (6) | C18—C21 | 1.504 (6) |
C5—C6 | 1.388 (6) | C18—C20 | 1.523 (6) |
C5—H5 | 0.9300 | C18—C19 | 1.531 (6) |
C6—C7 | 1.363 (8) | C19—H19A | 0.9600 |
C6—H6 | 0.9300 | C19—H19B | 0.9600 |
C7—C8 | 1.355 (7) | C19—H19C | 0.9600 |
C7—H7 | 0.9300 | C20—H20A | 0.9600 |
C8—C9 | 1.389 (5) | C20—H20B | 0.9600 |
C8—H8 | 0.9300 | C20—H20C | 0.9600 |
C9—H9 | 0.9300 | C21—H21A | 0.9600 |
C10—C11 | 1.504 (9) | C21—H21B | 0.9600 |
C10—H10A | 0.9700 | C21—H21C | 0.9600 |
C1—S1—C10 | 100.0 (3) | C12—C11—H11A | 108.9 |
O2—S2—N1 | 111.01 (15) | C10—C11—H11A | 108.9 |
O2—S2—C18 | 105.33 (16) | C12—C11—H11B | 108.9 |
N1—S2—C18 | 98.15 (17) | C10—C11—H11B | 108.9 |
C3—N1—S2 | 114.4 (2) | H11A—C11—H11B | 107.7 |
C3—N1—H1 | 114 (3) | C13—C12—C17 | 120.0 |
S2—N1—H1 | 113 (3) | C13—C12—C11 | 119.5 (4) |
O1—C1—C2 | 120.8 (4) | C17—C12—C11 | 120.3 (4) |
O1—C1—S1 | 125.0 (4) | C12—C13—C14 | 120.0 |
C2—C1—S1 | 114.2 (3) | C12—C13—H13 | 120.0 |
F1—C2—C3 | 110.1 (3) | C14—C13—H13 | 120.0 |
F1—C2—C1 | 110.3 (3) | C15—C14—C13 | 120.0 |
C3—C2—C1 | 112.0 (3) | C15—C14—H14 | 120.0 |
F1—C2—H2 | 108.1 | C13—C14—H14 | 120.0 |
C3—C2—H2 | 108.1 | C14—C15—C16 | 120.0 |
C1—C2—H2 | 108.1 | C14—C15—H15 | 120.0 |
N1—C3—C2 | 107.3 (3) | C16—C15—H15 | 120.0 |
N1—C3—C4 | 111.1 (3) | C17—C16—C15 | 120.0 |
C2—C3—C4 | 113.1 (3) | C17—C16—H16 | 120.0 |
N1—C3—H3 | 108.4 | C15—C16—H16 | 120.0 |
C2—C3—H3 | 108.4 | C16—C17—C12 | 120.0 |
C4—C3—H3 | 108.4 | C16—C17—H17 | 120.0 |
C5—C4—C9 | 118.6 (4) | C12—C17—H17 | 120.0 |
C5—C4—C3 | 120.3 (4) | C21—C18—C20 | 111.7 (3) |
C9—C4—C3 | 121.1 (3) | C21—C18—C19 | 112.0 (4) |
C4—C5—C6 | 120.9 (5) | C20—C18—C19 | 110.7 (3) |
C4—C5—H5 | 119.6 | C21—C18—S2 | 110.6 (2) |
C6—C5—H5 | 119.6 | C20—C18—S2 | 104.3 (3) |
C7—C6—C5 | 119.9 (5) | C19—C18—S2 | 107.2 (3) |
C7—C6—H6 | 120.1 | C18—C19—H19A | 109.5 |
C5—C6—H6 | 120.1 | C18—C19—H19B | 109.5 |
C8—C7—C6 | 120.2 (4) | H19A—C19—H19B | 109.5 |
C8—C7—H7 | 119.9 | C18—C19—H19C | 109.5 |
C6—C7—H7 | 119.9 | H19A—C19—H19C | 109.5 |
C7—C8—C9 | 120.4 (5) | H19B—C19—H19C | 109.5 |
C7—C8—H8 | 119.8 | C18—C20—H20A | 109.5 |
C9—C8—H8 | 119.8 | C18—C20—H20B | 109.5 |
C4—C9—C8 | 120.0 (4) | H20A—C20—H20B | 109.5 |
C4—C9—H9 | 120.0 | C18—C20—H20C | 109.5 |
C8—C9—H9 | 120.0 | H20A—C20—H20C | 109.5 |
C11—C10—S1 | 113.7 (4) | H20B—C20—H20C | 109.5 |
C11—C10—H10A | 108.8 | C18—C21—H21A | 109.5 |
S1—C10—H10A | 108.8 | C18—C21—H21B | 109.5 |
C11—C10—H10B | 108.8 | H21A—C21—H21B | 109.5 |
S1—C10—H10B | 108.8 | C18—C21—H21C | 109.5 |
H10A—C10—H10B | 107.7 | H21A—C21—H21C | 109.5 |
C12—C11—C10 | 113.5 (6) | H21B—C21—H21C | 109.5 |
O2—S2—N1—C3 | −89.5 (3) | C6—C7—C8—C9 | 0.4 (7) |
C18—S2—N1—C3 | 160.6 (3) | C5—C4—C9—C8 | 0.1 (6) |
C10—S1—C1—O1 | −3.1 (5) | C3—C4—C9—C8 | −177.3 (3) |
C10—S1—C1—C2 | 178.4 (3) | C7—C8—C9—C4 | −0.5 (6) |
O1—C1—C2—F1 | −175.4 (4) | C1—S1—C10—C11 | −95.7 (6) |
S1—C1—C2—F1 | 3.2 (4) | S1—C10—C11—C12 | −59.0 (7) |
O1—C1—C2—C3 | 61.6 (5) | C10—C11—C12—C13 | 106.0 (5) |
S1—C1—C2—C3 | −119.8 (3) | C10—C11—C12—C17 | −68.3 (5) |
S2—N1—C3—C2 | 159.9 (2) | C17—C12—C13—C14 | 0.0 |
S2—N1—C3—C4 | −75.9 (3) | C11—C12—C13—C14 | −174.4 (4) |
F1—C2—C3—N1 | 62.7 (4) | C12—C13—C14—C15 | 0.0 |
C1—C2—C3—N1 | −174.2 (3) | C13—C14—C15—C16 | 0.0 |
F1—C2—C3—C4 | −60.2 (4) | C14—C15—C16—C17 | 0.0 |
C1—C2—C3—C4 | 62.8 (4) | C15—C16—C17—C12 | 0.0 |
N1—C3—C4—C5 | 135.5 (4) | C13—C12—C17—C16 | 0.0 |
C2—C3—C4—C5 | −103.6 (4) | C11—C12—C17—C16 | 174.3 (4) |
N1—C3—C4—C9 | −47.1 (4) | O2—S2—C18—C21 | −57.3 (3) |
C2—C3—C4—C9 | 73.7 (4) | N1—S2—C18—C21 | 57.2 (3) |
C9—C4—C5—C6 | 0.4 (6) | O2—S2—C18—C20 | 62.9 (3) |
C3—C4—C5—C6 | 177.8 (4) | N1—S2—C18—C20 | 177.4 (3) |
C4—C5—C6—C7 | −0.5 (7) | O2—S2—C18—C19 | −179.7 (3) |
C5—C6—C7—C8 | 0.1 (7) | N1—S2—C18—C19 | −65.2 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O2i | 0.80 (2) | 2.32 (2) | 3.079 (4) | 159 (3) |
C2—H2···O2i | 0.98 | 2.42 | 3.265 (4) | 144 |
C10—H10B···O1ii | 0.97 | 2.58 | 3.473 (7) | 153 |
C21—H21B···O2iii | 0.96 | 2.57 | 3.475 (5) | 157 |
C21—H21A···F1iv | 0.96 | 2.55 | 3.465 (5) | 159 |
Symmetry codes: (i) −x, y+1/2, −z+2; (ii) −x, y+1/2, −z+1; (iii) x, y+1, z; (iv) −x, y−1/2, −z+2. |
Funding information
The authors thank the Innovation Program of Shanghai University Students (cx1704001) for financial support.
References
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