The information given below was retrieved and reworked from the publication: Use of the Chiral Pool - Practial Asymmetric Organocatalytic Strecker Reaction with Quinine by Rüdiger Reingruber, Thomas Baumann, Stefan Dahmen and Stefan Bräse. https://doi.org/10.1002/adsc.200800798The reaction was conducted according to the general procedure for preparation of N-carbamyl-α-(phenylsulfonyl)amines Method B: A mixture of the carbamate (2.00 equiv) and benzenesulfinic acid salt (1.50 equiv.) was suspended in a mixture of toluene/acetonitrile (1:1). Afterwards, the specific aldehyde (1.00 equiv.) was added in one portion, followed by formic acid (98%, 1.50 equiv.) and TMSCl (1.10 equiv.). The resulting mixture was allowed to stir for 24 h at 50 °C. After completion, the mixture was cooled down to 0 °C and treated with water. The resulting solution was extracted with diethyl ether, washed with brine, dried over MgSO4 and concentrated in vacuo. The resulting precipitate was filtered off and washed with water and diethyl ether. The precipitate was then recrystallized from CH2Cl2/hexane to obtain the title compound as a crystalline material.Analysis of the target compound: The title compound could be obtained in 84% yield as a white solid (mp 150–152 °C); 1H NMR (400 MHz, CDCl3): δ = 7.86 (d, J = 7.7 Hz, 2 H, Ar-H), 7.60 (t, J = 7.3 Hz, 1 H, Ar-H), 7.46–7.44 (m, 7 H, Ar-H), 7.27–7.26 (m, 3 H, Ar-H), 7.11 (d, J = 5.9 Hz, 2 H, Ar-H), 5.96 (d, J = 10.8 Hz, 1 H, NH), 5.76 (d, J = 10.1 Hz, 1 H, CH), 2.91 (dd, J = 65.1, 13.6 Hz, 2 H, CH2), 1.29 (s, 3 H, CH3), 1.19 (s, 3 H, CH3) ppm; 13C NMR (100 MHz, CDCl3): δ = 153.5, 136.9, 136.7, 133.9, 130.5, 129.9, 129.4, 129.0, 128.8, 128,7, 128.0, 126.5, 83.2, 73.9, 46.5, 26.0, 25.7 ppm; IR (KBr): v = 3362 (m), 3068 (w), 3017 (w), 2991 (w), 2956 (w), 2937 (w), 2914 (w), 1966 (vw), 1699 (m), 1512 (m), 1454 (m), 1320 (m), 1257 (m), 1203 (m), 1146 (m), 1083 (m), 975 (w), 880 (w), 690 (m), 625 (m), 572 (m) cm–1; MS (70 eV, EI), m/z (%): 424 (0.5) [M+], 293 (0.4), 142 (6), 133 (16), 132 (100), 117 (5), 91 (22), 77 (16), 58 (5), 43 (15).
