N-bromobutanimide → Ethyl 3-cyclopropyl-2-oxopropanoate

Participants

Reaction Steps

Preferably R3 is methyl, ethyl or isopropyl. Most preferably R3 is ethyl and the compound of Formula 5 is prepared by (a) reacting bromomethylcyclopropane with 2-carboethoxy-1,3-dithiane in the presence of a strong base to give ethyl 2-(cyclopropylmethyl)-1,3-dithiane-2-carboxylate; (b) reacting the ethyl 2-(cyclopropylmethyl)-1,3-dithiane-2-carboxylate with N-bromosuccinimide to give ethyl 3-cyclopropyl-2-oxopropanoate; and (c) reacting the ethyl 3-cyclopropyl-2-oxopropanoate with bis(2-methoxyethyl)aminosulfur trifluoride.

Provenance & Evidence