Studies on the synthesis of furan derivatives. 53. The reaction of 1-chloro-3-phenyl-2-propyne and 1,2-dichloro-3-phenyl-2-propene with triphenyl-phosphine and the preparation of related compounds

Abstract

Reaction of phenylpropargyl chloride (1) and triphenylphosphine, in the presence of hydrochloric acid, afforded 2-chlorocinnamyltriphenylphosphonium chloride (5), which was also obtained from α-chlorocinnamyl chloride and triphenylphosphine. The reaction of 1 in the absence of hydrochloric acid, gave 3-phenyl-1, 2 -propadienyltriphenylphosphonium chloride (2), which was also obtained by the reaction of 5 with an equimolar amount of sodium tert-butoxide. The Wittig reaction of the phosphonium salt (2 or 5) with 5-nitro-2-thenaldehyde, 5-nitrofurfural, p-nitrobenzaldehyde, or phenyl(p-nitrophenyl)-propargylaldehyde, in the presence of sodium methoxide as a base, resulted in the formation of the corresponding methoxyolefins but the use of sodium tert-butoxide gives only enynes, although this reaction with p-nitrobenzaldehyde afforded the corresponding cumulene (25).