Studies on selective cleavages of small membered rings with $SmI_2$

Abstract

The usefulness of $SmI_2$ as a versatile reagent in organic synthesis has been demonstrated by its widespread application for reduction of various functional groups, as well as its mediation of a range of promoting numerous synthetic transformations for the construction of complex organic compounds. The development of novel sequential reactions mediated by $SmI_2$ with high degree of stereo- and regioselectivity has been described. A new and convenient method of iodination with samariumiodide complex has been developed. The present reaction provides an efficient method for the synthesis of iodohydrins in a regio- and stereoselective manner. It has been found that epoxides have cleaved to iodohydrins with catalytic amount of samariumiodide complex in a regio- and stereoselective manner. A novel method for tandem epoxide opening-iodocyclization reaction has been developed using catalytic amount of samariumiodide complex under neutral and mild conditions. The reaction provides the acetals, THF, and THP derivatives with good yields. An aziridino alcohol opening reaction using catalytic amount of samarium diiodide complex has been developed with regio- and stereoselective manner.