[35495-31-9] · C3H5BrO2S · a-Bromovinyl Methyl Sulfone · (MW 185.05)
Physical Data: bp 63-64 °C/0.4 mmHg.
Solubility: sol common organic solvents.
Form Supplied in: colorless liquid; not commercially available.
Preparative Method: prepared by bromination-dehydrobromination of methyl vinyl sulfone in 80% yield.1
The reaction of a-bromovinyl methyl sulfone with cyclopentadiene affords a mixture of the expected cycloadducts which, upon treatment with Sodium Methoxide in DMSO, give 5-methylene-2-norbornene via the Ramberg-Bäcklund rearrangement in over 90% yield. Using 2N Sodium Hydroxide as the base, the adducts give, besides the expected 5-methylene-2-norbornene, 37-59% yield of the rearranged adduct (eq 1).1 The latter product arises from a radical rearrangement.
The action of Dimethyl Sulfoxide and a primary amine on a-bromovinyl methyl sulfone gives aziridines (eq 2).2
Ottorino De Lucchi
Università di Venezia, Italy
Istituto CNR, IPATCAPA, Sassari, Italy