An Approach to 3-Oxa-7-azabicyclo[3.3.0]octanes – Bicyclic Morpholine Surrogates

An approach to 3-oxa-7-azabicyclo[3.3.0]octanes, bicyclic morpholine analogues, is reported, which relies on [3+2] cycloaddition of maleic anhydrides or furan-2(5H)-ones and an in situ generated azomethine ylide. The utility of the method was demonstrated on a multigram scale.