Here,
we present an unprecedented formal [3 + 2] cycloaddition
of <i>para</i>-quinone methides with vinyl epoxides/cyclopropanes
to deliver a wide range of spiro[4.5]decanes in high efficiency and
stereoselectivity. The commercial availability of the catalysts and
reagents, together with the convenient procedure, makes it an attractive
method in asymmetric synthesis
