On a sulfurated grignard reagent equivalent to that of 2-chloromethyl-1,3-butadiene. New syntheses of ipsenol (2-methyl-6-methylene-7-octen-4-OL) and of (E)-β-farnesene ((E)-7,11-dimethyl-3-methylene-1,6,10-dodecatriene)

The Synthesis of Ipsenol and Ipsdienol: A Review (1968-2020)

Herein I present a review on the synthesis of ipsenol and ipsdienol, two aggregation pheromones of bark beetles, isolated from different species of genus Ips, and serious pests of conifer forests. I have covered the literature for around fifty years, since 1968 to 2020. This account has been divided in different sections and sub-sections, including a general and brief outlook on their isolation, structure and biological activity, to continue with the reported synthesis of racemic ipsenol and ipsdienol, including my own contribution to topic, and the presentation of reports describing the synthesis of enantiomerically pure ipsenol and ipsdienol. Particular attention has been devoted to identify and highlight racemic or enantiomerically pure "isoprene synthons", and isoprenylation methods employed in the synthesis of ipsenol and ipsdienol, of general interest for related terpene derivatives synthesis.