A Short and Efficient Synthesis of 4,5-Disubstituted-1-pentenes

Article abstract of DOI:10.1055/s-1986-31594

A one step synthesis of 5-chloro-4-hydroxy-1-pentene (65percent) and 5-bromo-4-hydroxy-1-pentene (81percent) was developed.Treatment of epibromohydrin or epichlorohydrin at -73 deg C with a reagent prepared from vinylmagnesium bromide and a catalytic amount of copper(I) bromide gave the desired products. 5-Bromo-4-hydroxy-1-pentene in was cleanly converted to 4,5-epoxy-1-pentene in 99percent yield by treatment with potassium hydroxide.A number of derivatives of 5-bromo-4-hydroxy-1-pentene are described.