Role of keto-enol tautomerization in a chiral phosphoric acid catalyzed asymmetric thiocarboxylysis of meso-epoxide: a DFT study.
- Citation data:
Organic & biomolecular chemistry, ISSN: 1477-0539, Vol: 13, Issue: 45, Page: 10981-5
- Publication Year:
- Chemistry; Biochemistry, Genetics and Molecular Biology
The mechanism of a chiral phosphoric acid catalyzed thiocarboxylysis of meso-epoxide was investigated by density functional theory (DFT) calculations (M06-2X). The nucleophilic ring opening of epoxide by thiobenzoic acid was found to proceed via a concerted termolecular transition state with a simultaneous dual proton transfer to yield the β-hydroxy thioester product. Electrostatic interactions together with the steric environment inside the chiral catalyst play an important role in determining the enantioselectivity of the reaction.