Tris(2-chloroethyl) phosphite → E-2-formylamino-4-methyl-5-di(2-chloroethyl)phosphono-3-pentenoic acid ethyl ester

Participants

Reaction Steps

8.2 g of E-5-bromo-2-formylamino-4-methyl-3-pentenoic acid ethyl ester and 19 ml of tris-(2-chloroethyl)-phosphite are stirred at a bath temperature of 70° for 20 hours. The resulting mixture is chromatographed on silica gel using ethyl acetate and ethyl acetate/isopropanol (7:1) as eluant, and the product is crystallised from ethyl acetate/diethyl ether. In this manner there is obtained E-2-formylamino-4-methyl-5-di(2-chloroethyl)phosphono-3-pentenoic acid ethyl ester, m.p. 47°-49°.

Provenance & Evidence