Phosphafluorenyl lithiums: direct synthesis from white phosphorus, structure and diversified synthons

While rich chemistry of phospholyl anions is discovered, phosphafluorenyl anions are only proposed as the critical intermediates for the synthesis of phosphafluorenes. In this article, we reported the direct synthesis of phosphafluorenyl lithiums from white phosphorus (P4) through direct P–C bond formation. The reaction between P4 and biphenyl dilithio reagents efficiently afforded phosphafluorenyl lithiums, which were further used to synthesize different kinds of organophosphorus compounds. The aggregation states of phosphafluorenyl lithiums were investigated for the first time. Mechanistic studies by DFT calculations revealed a cooperative nucleophilic attack of two C−Li bonds on P4 molecule.