Choichiro Hirai

Water-Soluble Calixarenes as New Inverse Phase-Transfer Catalysts. Their Scope in Aqueous Biphasic Alkylations and Mechanistic Implications

Alkylation reactions of active methylene compounds, alcohols and phenols with alkyl halides in aqueous NaOH solution can be carried out without the need for any added organic solvents in most cases. The water-soluble calix[n]arenes, which contain trimethylammoniomethyl groups on the upper rim, were used as inverse phase-transfer catalysts, resulting in the corresponding alkylated products in good to high yields. The scope of this methodology in aqueous biphasic alkylation reactions and the mechanistic implications are discussed.

WATER-SOLUBLE CALIXARENES AS NEW INVERSE PHASE-TRANSFER CATALYSTS. NUCLEOPHILIC SUBSTITUTION OF ALKYL AND ARYLALKYL HALIDES IN AQUEOUS MEDIA

The water-soluble calix[n]arenes 1 n (n = 4, 6 and 8) containing trimethylammoniomethyl groups act as efficient inverse phase-transfer catalysts in the nucleophilic substitution reaction of alkyl and arylalkyl halides with nucleophiles in water.