Highly stereocontrolled construction of tricyclo[6.2.2.0]dodecanes by intramolecular double Michael reaction
Abstract
o-Anisaldehyde has been converted, via a [3,3]sigmatropic reaction and a Birch reduction, into the cyclohexenone (10) bearing an α,β-unsaturated group. Treatment of the latter with lithium hexamethyldisilazide induced an intramolecular double Michael reaction to give the tricyclo[6.2.2.01,6]dodecane derivative (12)(60%) as a single isomer. The annelation of (20) also yielded the corresponding tricyclic compound (21)(50%).