Sunlight photocatalyzed regioselective β-alkylation and acylation of cyclopentanones

Sunlight-induced direct regioselective beta-alkylation of cyclopentanones with electron-deficient alkenes was accomplished by using tetrabutylammonium decatungstate (TBADT) as the catalyst. The regiochemistry can be rationalized by a polar transition state for an S(H)2 reaction. In the presence of CO, the reaction gave the three-component beta-acylation product in good yield.