CONTRIBUTIONS TO THE CHEMISTRY OF PHOSPHORUS .234. LITHIUM TETRAHYDROGEN CYCLOPENTAPHOSPHIDE - SYNTHESIS, STRUCTURE AND REACTIONS

Lithium tetrahydrogen cyclopentaphosphide, LiH4P5 (1), has been obtain ed by metalation of P2H4 at -78 degrees C with either n-BuLi or LiPH2 in polar solvents. Upon suitable performance of the reaction, compound 1 can be isolated at low temperature as a lemon-yellow solvent adduct . The structure as the monolithium salt of (PH)5 was confirmed by a co mplete analysis of the P-31{H-1}-NMR spectrum. On warming above -35 de grees C, disproportionation occurs yielding Li2HP7, P2H4, and PH3. The reaction with n-BuLi produces the open-chain phosphides LiH4P3, LiH3P 2, and LiPH2. The NMR parameters of LiH3P2 and LiH4P3 are reported. Re action of 1 with P2H4 gives rise to the bicyclic and polycyclic phosph ides LiH4P7, LiH5P8, and Li2H2P14, respectively.