Mono-and Bicyclic Cyclopentenes by Rearrangement of 1-Methylcyclobutylmethanols: Synthesis of (±)-Cuparene and Formal Syntheses of (±)-Laurene and (±)- …
Abstract: Addition of 1-methylcyclobutylmagnesium chloride (3) to acyclic (4d, e) and cyclic ketones (4a–c) yields 1-methylcyclobutylmethanols (5a–e), which may be rearranged to mono-(11–14) and bicyclic cyclopentenes (6–10), respectively. Compounds 11, 12, and 13 are known precursors of (±)-laurene (15),(±)-cuparene (16), and (±)-herbertene (17), respectively. The cyclopentene 11 has been used in a two step synthesis of (±)-cuparene ( ...