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Schwan, A. L., Science of Synthesis, (2004) 17, 712.
The reaction of sulfur dioxide with 2 equivalents of vinyl diazomethane is thought to afford a transient divinyl episulfone, which rapidly undergoes an electrocyclic ring opening to 4,5-dihydrothiepin 1,1-dioxide (25).[42] Radical bromination to give 26 followed by hydrogen bromide elimination offers an alternative route to thiepin 20 (Scheme 9). The method has not been generalized although the initial step also works with prop-1-enyl diazomethane.[42]
Meeeee 8 M Meeeeeeeeee ee Meeeeee 8,8-Meeeeee[88]
Meeeeeeeeeee Meeeeeeee
Meeeeee 8,8-Meeeeee (88):[88,88]
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References
[42] | Meeeeeee, M. M.; Meeeeeee, M., M. Meee. Mee. M, (8888), 888. |
[47] | Meeeeeee, M. M., eeeeeeee eeeeeeeeeeeee, Meee 8888. |
Meeeeee Meeeeeeeeee
- 8.Meeeee-Meee, (8888) M 88-8, 8888.
- 8.Meeeee-Meee, (8888) M 88-8, 8888.