5. Two frequently encountered alkenyl groups are the vinyl group and the allyl group H2c C=g—c H3C—Hc=c The vinyl group团乙烯基) The ally group(烯丙基) The Propylene group两丙烯基) CH2Cl -CH2Br IUPAC: Bromoethene IUPAC: 3-Chloropropene IUPAC: 3-Bromopropene Common; vinyl bromide Common; allyl chloride Common; allyl bromide (乙烯基溴) (烯丙基氯) (烯丙基溴)5. Two frequently encountered alkenyl groups are the vinyl group and the allyl group. The vinyl group (乙 烯 基 ） The ally group (烯 丙 基 ） H2C C H H2C C H CH2 HC C H2 H3C The Propylene group (丙 烯 基 ） Br CH2Cl IUPAC: Bromoethene Common; vinyl bromide (乙烯 基 溴 ） IUPAC: 3-Chloropropene Common; allyl chloride (烯 丙 基 氯 ） CH2 Br IUPAC: 3-Bromopropene Common; allyl bromide (烯 丙 基 溴 ）