ChemInform Abstract: Microwave‐Assisted Green Synthesis of Novel Spiro Isoxazolidine Derivatives with α‐Chloro Nitrones.

Abstract

The use of microwaves in organic synthesis has increased dramatically within the past decade, receiving widespread acceptance and becoming an indespensible tool 1 . Microwave technology has become a powerful tool in organic synthesis, since by employing this technique it is generally possible to prepare organic compounds very fast with high purity and better yields compared to other more conventional methods 2 . Microwave irradiation can be used as a facile and general method for the construction of a variety of isoxazolidine and isoxazoline derivatives where considerably shortened reaction time is involved 3 . In continuation of the green methodological synthesis of isoxazolidine, isoxazoline, aldehyde synthesis using α-amino and α-chloro nitrones in solid phase and in hydrated media 4-13 , herein is reported for the first time, novel α-N-methyl/phenyl furan derivatives (obtained as side product during aldehyde synthesis) 4,10,12 as dipolarophile in the regioselective synthesis of 5-spiro isoxazolidines using αchloro nitrones under microwave irradiation with an excellent yield (Scheme I, Table I). The reported regionselectivity study has been compared with cycloaddition reaction of α-chloro nitrones with αmethylene-γ-butyrolactone and has been found to give diastereoselective 5-spiro isoxazolidines (Scheme II, Table I).