Annelative ring expansion via intramolecular [2 + 2] photocycloaddition of .alpha.,.beta.-unsaturated .gamma.-lactones and reductive cleavage: synthesis of hydrocyclopentacyclooctene-5-carboxylates
Synthesis of decahydrocyclopentacyclo-octene derivatives via intramolecular photocycloaddition of Δ<sup>α,β</sup>-butenolides and reductive cleavage
作者:William R. Baker、Peter D. Senter、Robert M. Coates
DOI:10.1039/c39800001011
日期:——
and penta-3,4-dienyl side-chains in the γ-position, (2) and (3), effected intramolecular [2 + 2] cycloaddition to form fused tricyclic lactones (4) and (5), respectively, as major products; reductive ring opening of the derived keto-acid (7a) and keto-ester (9) gave the octa- and deca-hydrocyclopentacyclo-octene derivatives (8) and (10) respectively.