טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
Ph.D Thesis
Ph.D StudentSklute Genia
SubjectDevelopment of Allylation Reactions for the Asymmetric
Construction of Quaternary Stereocenters
DepartmentDepartment of Chemistry
Supervisor Professor Ilan Marek
Full Thesis textFull thesis text - English Version


Abstract

The complexity of organic molecules required by the community is constantly increasing, and novel strategies, allowing the efficient asymmetric formation of quaternary stereocenters are needed. Despite the tremendous progress in this area, a much larger panel of reactions, achieving a significant increase in structural complexity per chemical steps, is necessary. This is particular true for transformations, which involve more than one bond-making event.

            In this manuscript, we would like to describe new strategies for the asymmetric construction of quaternary stereocenters in a single-pot operation, stereoselective functionalization of cyclopropane derivatives using bromine/magnesium and sulfoxide/magnesium exchange reactions, along with a new route for the synthesis of polysubstituted vinyl sulfoximines. To meet these challenging problems, we have developed a new route for the preparation stereodefined allylzinc species that bears chiral auxiliary. Four different approaches for the asymmetric synthesis of homoallylic alcohols possessing quaternary stereocenters were developed. Then, we examined the possibility to use an external source of chirality, which led to the asymmetric synthesis of quaternary stereocenters from chiral sulfinylimines. In addition to this, we have developed a new route to polysubstituted vinyl sulfoximines and sulfones, through the regio- and stereoselective copper-catalyzed carbozincation of the corresponding alkynes.