86280-13-9Relevant academic research and scientific papers
Rearrangements of the Methyltrimesitylphosphonium and Methylenebis(methyldimesitylphosphonium) Cation Skeletons on Treatment with Base
Schmidbaur, Hubert,Schnatterer, Stefan
, p. 1947 - 1954 (2007/10/02)
The treatment of methyltrimesitylphosphonium iodide (1) with sodium amide or butyllithium leads neither to the corresponding phosphorus ylide nor to the product of a Stevens rearrangement, but affords instead methylmesitylphosphane (4).The product, which is probably formed via a mesityl migration in an 2-methylenecyclohexadienylidenephosphorane intermediate (2b), is structurally characterized by detailed NMR analysis and through hydrochloride and methoiodide derivatives. - Analogous treatment of methylenebis(methyldimesitylphosphonium iodide) (10) with base leads to a pair of diastereomeric cyclic carbodiphosphoranes (12a, b), with elimination of mesitylene.The two carbodiphosphoranes are converted into the diastereomeric diphosphonium salts 13a, b with HCl.The ring closure leading to carbodiphosphorane formation is again interpreted in terms of an intramolecular process involving an 2-methylenecyclohexadienylidene intermediate.Deprotonation of the methylenebis(methyldi-o-tolylphosphonium) cation yields the corresponding carbodiphosphorane 18 without changes in the skeleton.
