Triphenylphosphine-grafted, RAFT-synthesised, porous monoliths as catalysts for Michael addition in flow synthesis

Abstract

We describe the preparation and application of triphenylphosphine functional polystyrene-based porous monolithic catalysts for use as flow reactors. RAFT (reversible addition-fragmentation chain transfer)-crosslinking polymerisation of styrene and divinylbenzene provided monoliths which were then functionalized by RAFT "grafting from" polymerisation of 4-styryldiphenylphosphine mediated by the retained thiocarbonylthio functionality. Under the chosen conditions, the retention of the RAFT functionality was proved by chain extension experiments in which the monoliths were five times re-subjected to the grafting conditions. Importantly, the bound triphenylphosphine-functionality was demonstrate..