Intramolecular γ C–H insertion vs. olefin cycloaddition in 4-methylene-2-adamantylidene and 8-methylene-2-noradamantylidene
Abstract
8-Methylene-2-noradamantylidene inserts readily into the γ C–H bond giving 6-methylene-2,4-didehydro-noradamantane rather than the olefin-cycloaddition product, while its higher homolouge 4-methylene-2-adamantylidene reacts exclusively by intramolecular cycloaddition to the olefinic bond yielding 2,4-methano-2,4-didehydroadamantane, a [3.1.1.]propellane.