1-CHLORO-2-BUTENE 1-Chlorobut-2-ene 2-01-00-00176 (Beilstein Handbook Reference) 2-Butene, 1-chloro- 2-Butenyl chloride 591-97-9 BRN 0605304 Crotyl chloride EINECS 209-739-5 Krotylchlorid [Czech] gamma-Methallyl chloride gamma-Methylallyl chloride