A GREEN REGIO- AND DIASTEREOSELECTIVE SYNTHESIS OF NOVEL TRISPIROHETEROCYCLES IN 2,2,2-TRIFLUOROETHANOL

摘要

A new regio- and diastereoselective 1,3-dipolar cycloaddition reaction of 7,9-bis[(E)arylidine]-1,4-dioxa-spiro[4,5]decane-8-ones, sarcosine/1,3-thiazolane-4-carboxylic acid and acenapthequinone has been developed for the synthesis of trispiropyrrolidine/thiapyrrolizidine derivatives using 2,2,2-trifluoroethanol as a green solvent. The solvent (TFE) can be readily separated from reaction products and recovered in excellent purity for direct reuse. A regio- and stereochemical outcome of the cycloaddition reaction was ascertained by X-ray crystallographic study.