Benzyl Alcohol → 2-(N-carbobenzyloxyaminosulfonyl)aminopentanoic acid methyl ester

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Reaction Steps

To a stirred solution of 14.72 ml (0.17 mol) of chlorosulfonyl isocyanate in 400 ml of methylene chloride was added 5 benzyl alcohol (17.69 ml, 0.17 mol) at 0-5° C. After stirring the above solution for 1.5 hours at this temperature, a solution of 31.24 g (0. 186 mol) of 2-amino-pentanoic acid methyl ester hydrochloride in 1100 ml of methylene chloride containing triethylamine (51.08 g, 0.5 mol) was added at 0°-5° C., and the resulting mixture was stirred overnight allowing the mixture to warm to room temperature. The reaction mixture was poured into 600 ml of 10% aq. HCl solution, saturated with sodium chloride, and the organic layer was separated. The aqueous layer was extracted with methylene chloride/ethyl acetate (4:1) and the combined organic layer was washed with brine, dried and concentrated in vacuo to yield 47.7 g (82%) of 2-(N-carbobenzyloxyamino-sulfonyl) aminopentanoic acid methyl ester (Formula XIV: R=CH3 ; R1 =H; R2 =propyl; R3 =H) as a solid, m.p. 76°-78° C.

Provenance & Evidence