Search for the new reactivity of aldehydes

Abstract

1.Br$\o$nsted acid-mediated diastereoselective silyl-oxa-Prins cyclization Multisubstituted tetrahydropyranols is a versatile building block in organic synthesis because of their interesting biological activities. We developed an efficient synthetic route to tetrahydropyranols through diastereoselective silyl-oxa-Prins cyclization of α-silyloxy homoallylsilanes with various aldehydes mediated by Brønsted acids. Synthetically valuable tetrahydropyranol products were obtained in high yields with excellent diastereoselectivities. Both syn and anti diastereomers of tetrahydropyranols were selectively obtained by tuning the olefinic geometry of the homoallylsilane substrates. The procedure is operationally simple and large scale reaction was also smoothly performed under mild conditions. 2.(NHC)Cu-catalyzed Borylative Cross-coupling of Olefin and Aldehyde Functionalized organoboron compounds are useful building block utilized in synthesis of various functional molecules and medicines. We herein present the study of (NHC)Cu-catalyzed borylative cross coupling reaction of styrenic olefins and benzaldehydes. The Borylative cross-coupling were more efficient with the electron-deficient styrenes. However, rather limited substrate scope and poor diastereoselectivity have been revealed as the obvious challenges for the future development of this synthetically useful reaction.