Cyclisation of bis(methylene)phosphoranes: a new way to five-membered heterocycles
Abstract
The catalytic rearrangement of the metallo-bis(methylene)phosphorane 1 in the coordination sphere of an iron atom furnishes two isomeric five-membered heterocycles 2 and 3 resulting from the incorporation of the C3H5 ligand and one of the P–C double bonds; a similar reactivity could be obtained in the reaction of the chlorobis(methylene)phosphorane 4 with AlBui3, which affords the 1H-λ5-methylenephospholane 6.