m-Tolyl isocyanate → HCID 86750530, compound

Participants

Reaction Conditions

Reaction Steps

0.8 cm3 of 3-methylphenyl isocyanate is added to a solution of 2.0 g of tert-butyl (2R,4R)-3-(2-aminoacetyl)-2-phenyl-4-thiazolidinecarboxylate in 25 cm3 of anhydrous tetrahydrofuran. The reaction mixture is stirred for 12 hours at a temperature in the vicinity of 25° C., then diluted with 100 cm3 of ethyl acetate. The organic phase is washed with 2 times 40 cm3 of water, dried over magnesium sulphate and concentrated to dryness under reduced pressure at 40° C. The crude product obtained is purified by chromatography on silica [eluent: methylene chloride/methanol (98/2 by volume)]. The fractions containing the expected product are combined and concentrated to dryness under reduced pressure at 40° C. After vigorous stirring in heptane, 0.5 g of tert-butyl (2R,4R)-3-{2-[3-(3-methylphenyl)ureido]acetyl}-2-phenyl-4-thiazolidinecarboxylate is thus obtained in the form of a white amorphous powder ([α]D20 =+70.0°±1.3° (C=1.02%; CHCl3)) [proton NMR (200 MHz, CDCl3, δ in ppm), 2 rotamers at room temperature, description for the preponderant rotamer at 25° C.: 1.45 (bs, 9H, (CH3)3); 2.2 (s, 3H, CH3); 3.2 (A2X, 2H, CH2S); 3.2 and 4.3 (ABX, 2H, CH2N); 4.9 (t, 1H, CHN); 6.1 (bdd, 1H, NH); 6.2 (s, 1H, SCHN); 6.8 to 7,7 (m, 9H, aromatic). Infrared spectrum (KBr), characteristic bands in cm-1 : 3375, 2975, 2930, 1735, 1650, 1610, 1595, 1560, 1490, 1455, 1370, 1150, 780, 730, 695].

Provenance & Evidence