2- Bromobutyryl bromide

Monoalkylketenes. Methylketene and ethylketene can be obtained in 60-65% yield by reaction of 2-bromopropionyl bromide and 2-bromobutyryl bromide in THF with zinc activated by treatment with hydrochloric acid (1, 1276) under reduced pressure (100 mm). The ketenes codistill with THF and are free from starting materials and zinc salts. The present method is a modification of Standinger s ketene synthesis, which gave only low yields of these ketenes. ... 

Bromobutyryl bromide, 674 Bromocamphor, 484, 675 to-Bromocarboxylic acids, 479 p-Bromochlorobenzene, 179... 

A series of l,3-benzo[e]thiazepines, a new class of heterocyclic compounds, have been synthesized by Reinhoudt by the reaction of 2-bromo-methylbenzyl or 2-bromomethylbenzoyl bromide with thioureas. Compound (325) was obtained in a similar way from NN -diphenylthiourea and 4-bromobutyryl chloride. Reinhoudt also found that the thioureas (326), on heating in acetone, underwent a ring-closure reaction to form either (327) or (328) (for R = H). The formation of (328) was considered to be a result of... 

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