A Change from Kinetic to Thermodynamic Control Enables trans-Selective Stereochemical Editing of Vicinal Diols
Yu-An Zhang1, Xin Gu1, Alison E Wendlandt1
1Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.
Abstract:
Here, we report the selective, catalytic isomerization of cis-1,2-diols to trans-diequatorial-1,2-diols. The method employs triphenylsilanethiol (Ph3SiSH) as a catalyst and proceeds under mild conditions in the presence of a photoredox catalyst and under blue light irradiation. The method is highly chemoselective, broadly functional group tolerant and provides concise access to trans-diol products which are not readily obtained using other methods. Mechanistic studies reveal that isomerization proceeds through a reversible hydrogen atom transfer pathway mediated by the silanethiol catalyst.
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