Adventures in Tin(II) phosphinidene chemistry; insights into the mechanism of P–P and Sn–Sn bond formation

The reactions of the Sn(II) dimethylamido reagent Sn(NMe2)2 with alkali metal primary phosphides [RPHM] give a range of heterometallic Sn(II) phosphinidene compounds, depending on the organic substituents (R) and the alkali metal (M). For less sterically demanding substituents and/or for the heavier alkali metals, the formation of P–P and Sn–Sn bonded complexes occurs. Structural studies of the reaction products with a range of R-groups and alkali metals cast light on the mechanisms involved in this new type of reaction.