Iron(iii)-induced tandem Nazarov cyclization–rearrangement of α-(trimethylsilylmethyl)divinyl ketone. Synthesis of the bicyclo[4.3.0]nonane ring system via spiro[4.4]nonane

Abstract

6-Methylbicyclo[4.3.0]non-8-en-7-one was synthesized by FeCl ₃ -induced tandem Nazarov cyclization–rearrangement of 4-cyclopentylidene-5-trimethylsilylpent-1-en-3-one, via 7-methyl-1-methylenespiro[4.4]nonan-2-one as intermediate.