Facile rotation around a silicon-phosphorus double bond enabled through coordination to tungsten

Abstract

Unprecedented E/Z isomerisation of a SiP bond was observed by temperature dependent NMR spectroscopy. DFT calculations showed that the coordination of phosphasilene to tungsten lowered the rotational barrier from 19.1 to 14.2 kcal mol-1. The thermodynamically more stable phosphinosilylene tungsten complex is formed at elevated temperatures through substituent migration.