A computational study of the formation and dimerization of benzothiet-2-one.

Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061, USA.
Organic Letters (Impact Factor: 6.14). 02/2008; 10(2):245-8. DOI: 10.1021/ol702628v
Source: PubMed

ABSTRACT A computational B3LYP/6-31G(d,p) study of the formation of benzothiet-2-one (4) from benzothiophenedione (2) and its subsequent dimerization to 5 was performed. The proposed intermediate ketene 3 has no gas-phase barrier to ring closure to 4. Three transition structures for dimerization were located. The geometry of the lowest energy one (TS8a) has a geometry corresponding to a two atom + two atom, face-to-face addition of the two thiolactone moieties. The orbital interactions suggest that the reaction is pseudopericyclic.