Science, Tech, Math › Science Alkenyl Group in Chemistry Share Flipboard Email Print The alkenyl functional group is a type of hydrocarbon functional group based on an alkene. It is characterized by its double bond. Ben Mills Science Chemistry Chemical Laws Basics Molecules Periodic Table Projects & Experiments Scientific Method Biochemistry Physical Chemistry Medical Chemistry Chemistry in Everyday Life Famous Chemists Activities for Kids Abbreviations & Acronyms Biology Physics Geology Astronomy Weather & Climate by Anne Marie Helmenstine, Ph.D. Updated May 14, 2018 An alkenyl group is a hydrocarbon group formed when a hydrogen atom is removed from an alkene group.Alkenyl compounds are named by replacing the -e from the parent alkene's name with -yl.Examples: H2C=CH- (ethenyl or commonly known as vinyl). The parent alkene was H2C=CH2, ethene. Continue Reading