Cycloaddition of enamines with alkynylphosphonates. A route to functionalized medium sized rings

Article abstract of DOI:10.1016/S0040-4039(00)73213-8

Substituted seven and eight membered rings were formed from cyclopentanone and cyclohexanone via cycloadditions of pyrrolidine enamines with alkynyl phosphonates. This procedure provides straightforward access to functionalized medium sized rings that could be further manipulated in the synthesis of a number of natural products.