Phosphafluorenyl Lithiums: Direct Synthesis from White Phosphorus, Structure and Diversified Synthons

Jingyuan Hu, Zhengqi Chai, Wei Liu, Zhe Huang, Junnian Wei, and Wen-Xiong Zhang*

Sci. China Chem. 2021, 65, 322–327

https://doi.org/10.1007/s11426-021-1139-0

      While rich chemistry of phospholyl anions is discovered, phosphafluorenyl anions are only proposed as the critical intermediates for the synthesis of phosphafluorenes. In this work, we reported the direct synthesis of phosphafluorenyl lithiums from white phosphorus (P₄) through direct P-C bonds formation. The reaction between P₄ and biphenyl dilithio reagents can efficiently afford 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 reveal a cooperative nucleophilic attack of two C−Li bonds on P₄ molecule.