No abstract

Olefins were effectively converted into the corresponding (2-methylthioalkyl)triphenylphosphonium salts by the reaction with dimethyl(methylthio)sulfonium salts in the presence of triphenylphosphine. 2-Triphenylphosphonioalkyldimethylsulfonium salts, synthesized by alkylation of the corresponding methylthiophosphonium salts, react with 1,8-diazabicyclo[5.4.0]undec-7-ene or aq NaOH to afford the corresponding vinylphosphonium salts or vinylphosphine oxides in good yields.

Triphenylvinylphosphonium salts were prepared by the reaction of 2-hydroxyalkyltriphenylphosphonium salts with acetyl chloride or oxalyl chloride. These salts were also synthesized by a one-pot operation of treating epoxides with triphenylphosphonium tetrafluoroborate, followed by the addition of acetyl chloride or oxalyl chloride successively. The reaction of these salts with 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and aromatic aldehydes afforded the corresponding dienes in moderate yields via α,β-unsaturated ylide intermediates.

Reactions of (dimethylamino)phenylsulfoxonium methylide with triphenylvinylphosphonium salts gave the corresponding cyclopropyltriphenylphosphonium salts (E-form) in high yields, when 1,8-diazabicyclo[5.4.0]undec-7-ene was used as a base. Reactions of cyclopropyltriphenylphosphonium salts with sodium hydride in the presence of tris[2-(2-methoxyethoxy)ethyl]amine afforded the corresponding ylides, which further reacted with aldehydes to give alkylidenecyclopropanes in high yields.

Aus dem Acrolein (III) erhält man mit Anilin (II) und dem Aminopyridin (IV) die Derivate (I) bzw. (V).