Nucleophilic ring opening of imidazolone activated donor–acceptor cyclopropanes with alcohols
Imidazolone-activated donor–acceptor cyclopropanes
undergo alcohol-assisted ring opening under the co-action of
p-toluenesulfonic acid. Under the optimized conditions,
cyclopropanes and alcohols are coupled in 1,3-fashion with
the retention of heterocyclic fragment. Substrates with
aromatic donor groups provide the addition products in
75–99% yields as mixtures of two diastereomers.