Thiocarbonyl compounds hydrogen abstraction and cycloaddition

In contrast to excited carbonyl compounds, which abstract hydrogen efficiently from the n,Jt state (Section 6.3.1), thiocarbonyl compounds react from both n,Jt and n,n states and the hydrogen atom can be added to either sulfur or carbon atom of the C=S bond.1259,1269,1270 The sulfur atom is larger than oxygen, therefore the reaction can occur 

Case Study 6.32 Mechanistic photochemistry - reactions from different excited states 

The same benzene solution was irradiated through a Pyrex filter (/.in 280 nm S2 excitation) to complete conversion and the product was isolated in 82% chemical yield. 

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