Proximal heteroalkylation of monoalkoxycalix[4]arenes in synthesis of inherently chiral molecules

Abstract

Proximal heteroalkylation of monoalkyl ethers of calix[4]arenes or p- tert-butylcalix[4]arenes in NaH/CH 3CN or NaOH/DMSO, respectively, was applied for synthesis of inherently chiral calixarenes with ABHH substitution pattern. The introduction by the method of ( R)- or ( S)- N-(α-phenylethyl)acetamide chiral auxiliary group gives mixtures of diastereomeric derivatives of inherently chiral calixarenes, which were separated by column chromatography. The chiral calixarenes were thoroughly characterized by 1H, 13C NMR, and X-ray diffraction methods.