Episulfones, from sulfones

Ethylene derivatives from sulfonic acid chlorides via sulfenes and episulfones... 

Values of the dipole moments of sulfones, including ethylene episulfone, were computed by Rozas at different computational levels (HF 6-31G and MP2 6-31G HF-6 31G ) and different methods of charge estimation <1997IJQ477>. Numbers ranged from 5.946 to 3.901 D. The experimental value of the dipole moment is 4.41 D. 

The Ramberg-Baddund reaction (RBR), in its most general form, generates an alkene, 2, from a sulfone, 1 (Scheme 8T). The process involves halogenation at the a-center of 1, abstraction of a proton from the nonhalogenated a-center of the resulting halosulfone 3, and cyclization to give an episulfone (thiirane 1,1-dioxide, 4), followed by extrusion of sulfur dioxide. 

The Michael-induced RBR exploits the electrophilic nature of vinyl-substituted sulfones. Upon nucleophilic attack, the alkene double bond migrates to form an episulfone intermediate by displacement of an a-halide fScheme R.12T The product alkene, resulting from subsequent SO2 extrusion, is transposed by one position from the original alkene. The a-halide may... 

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