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Coined (1860) by British chemist C. G. Williams, from iso- (“equal; different, isomeric”) + pr(op)- (“three carbon prefix”) + -ene (“alkene suffix”). A misnomer.
Etymology from Wiktionary, CC BY-SA 4.0.
isoprene
Today it means: An unsaturated hydrocarbon, C₅H₈, that is readily polymerized; natural rubber (caoutchouc) is cis-1,4-polyisoprene, and trans-1,4-polyisoprene is present in gutta-percha and balata; it is the structural basis for the terpenes. Full definition →