Total Synthesis of Biologically Active Natural Products Using Prins Cyclization Approach and Development of Novel Synthetic Methodlogies

Abstract

The coupling of an olefin with a carbonyl compound in the presence of an acid catalyst is newlineknown as the Prins reaction which normally provides a mixture of 1, 3-diols, 1, 3- newlinedioxanes, and allylic alcohols. In particular, the coupling of a homoallylic alcohol with a newlinecarbonyl compound in the presence of an acid catalyst is known as the Prins newlinecyclization , which is a powerful synthetic tool for the stereo selective synthesis of newlinetetrahydropyran scaffolds. On the other hand, aza-Prins cyclization of homoallylic amides newlinewith carbonyl compounds is one of the most elegant approaches for the synthesis of newlinepiperidine derivatives. In the same way, thia-Prins cyclization of homoallylic mercaptans newlinewith aldehydes under the influence of an acid catalyst provides the corresponding newlinethiotetrahydropyrans with a high selectivity. Thus, the Prins cyclization has emerged as a newlinepowerful method for the stereo selective synthesis of a wide range of heterocycles such as newlinetetrahydropyran, piperidine and thiotetrahydropyran scaffolds (Scheme-2). Many newlineresearch groups including work from our group have broadened the scope of Prins newlinecyclization via development of new methodologies (Scheme-1). newline