RAMBERG-BACKLUND-PAQUETTE Olefin

PAQUETTE Olefin Synthesis OesuHonatlon of suHones to alkenes (altemative to Ramberg-Backlund). 

PAQUETTE Olefin Synthesis Desulfonation o( sutfones to alkenes (alternative to Ramberg-Backlund). 

Treatment of a-halosulfones 357 bearing a -hydrogens with base gives olefins by extruding SO2 from the episulfone intermediates 359. The reaction was found by Ramberg and Backlund in 1940 and named after them, and it has been very useful for the preparation of tailor-made olefins. The reaction has been investigated in detail " and utilized widely for olefin syntheses. An excellent review on this reaction by Paquett covers the literature up to 1975, so only recent studies are dealt with in this section. The generally accepted mechanistic path is shown below. 

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