Stereoelectronic effects in conformations of sulfide, sulfoxide, and sulfone alpha-carbanions

摘要

Energy and stabilization of conformers of alpha-carbanions of sulfides, sulfoxides, and sulfones are calculated, where the most stable conformations in sulfide and sulfone a-carbanions are at 180, which benefit from strong n(c)- -> sigma(S-C)* stereoelectronic effects (91 and 59 kJ/mol). An n(c)- -> sigma(S-O)* interaction (79 kJ/mol) stabilizes the sulfoxide's minimum conformation at 60 degrees. (C) 2015 Elsevier Ltd. All rights reserved.