Sulfines, Wolff rearrangement

Irradiation at X > 375 nm of the two diastereomeric diazo sulfoxides 31a and 31b underwent hetero Wolff rearrangement affording the a-oxo sulfine 34. The carbene 32 has not been deteeted even in traces and the sulfine 34 is proposed to be formed from 31, via dediazotization, hetero Wolff rearrangement and isomerization of domino sequence. ... 

Wolff-like rearrangement of the carbenes (57) to the sulfines (59), which rearrange with loss of sulfur. The remaining minor products were postulated to arise by loss of PhsPO to give the sulfenyl carbene RS(Ph)C . 

Another instance of the sulfoxide as an interested spectator in a photochemical reaction is the generation of a-sulfinyl carbenes [115]. Photolysis (or thermolysis) of the sulfmyl substituted pyrazoline 227 was shown by trapping experiments to generate the carbene 228, which undergoes a Wolff-type rearrangement to generate the sulfine. After loss of sulfur, the ketone 230 is isolated in near quantitative yield. 

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