It has in fact been reported* that the bromination of 2, 3-dimethyl-1, 3-butadiene (5) at-15" gives two bromides, solid 7 (80%) stereochemistry unspecified, but probably trans considering steric effects) and a minor amount of a liquid dibromide (presumably 6), which could be interconverted at 100". We found that bromination of 5 at-10" yields two compounds with similar glc characteristics. They were initially present in comparable amounts, but ...