Dichloromethane → 1-t-Butoxycarbonyl-3,3-dimethylthiourea

Participants

Reaction Steps

44 (1.04 g, 10.0 mmol) and BOC2O (2.18 g, 10.0 mmol) were dissolved in a biphasic solution of CH2Cl2 (40 mL) and sat. NaHCO3 (40 mL) and the two layers stirred vigorously. After 24 h, the reaction mixture was diluted with CH2Cl2 (60 mL), water (60 mL) and the organic layer separated. The organic layer was washed with water (2×100 mL), dried (Na2SO4) and concentrated. The product oil was purified over silica gel (20% EtOAc/Hexane) to give a mixture of isomers of the product mono-BOC protected S—Me-isothiourea as a sticky oil (1.85 g, 90%). 1H-NMR (DMSO-d6) 9.45 (s, 0.4H), 8.97 (s, 1H), 3.17 (s, 3H), 3.06 (s, 1.2H), 2.33 (s, 1.2H), 2.23 (s, 3H), 1.45 (s, 9H), 1.39 (s, 3.6H).

Provenance & Evidence