Bildung und Reaktionen P-funktioneller Phosphane

Formation and Reaction of P-functional Phosphanes The reaction of (me₃Si)₂PLi · 2 THF a (me = CH₃) with PCl₃ b at ?78°C via the intermediate (me₃Si)₂P? PCl₂ 1 yields (me₃Si)₂P]₂PCl 2 and (me₃Si)₂P]₂P? P(Sime₃)₂ 3 . By addition of me₃CLi c to the reaction mixture of a and b (molar ratio a:b:c (molar ratio a:b:c = 1:1:1) at ?60°C, 2 is formed as a main product, which reacts on to yield (me₃Si)₂P]₂PH 4 (white crystals, mp = 73°C). By reactions of a:b:c in a molar ratio of 1:1:2 the cyclotetraphosphane (me₃C)₃ (me₃Si)P₄ 7 is accessible, and the additional formation of (me₃Si)₂PLi · 2 THF, (me₃Si)₃P and Li₃P₇ · 3 THF 13 was detected. Warming (me₃Si)₂P? PCl(Cme₃) 5 to 20°C produces cis- and trans-cyclotetraphosphanes (me₃Si)₂(me₃C)₂P₄. By running the reaction of a and b at ?78°C and adding me₃CLi only after 24 h, additionally to (me₃Si)₂P? PH Cme₃) and (me₃Si)₃P also (me₃Si)₂P? P(Cme₃)? P(Cme₃)? P (Sime₃)₂ is obtained, which is formed by metallation of (me₃Si)₂P? PCl(Cme₃) with me₃CLi and by further reaction of the intermediate (me₃Si)₂P? PLi(Cme₃) with (me₃Si)₂P? PCl(Cme₃). The reaction of (me₃Si₃)P with PCl₃ at ?78°C only yields (me₃Si)₂P? PCl₂ 1 and me₃SiCl. On addition of me₃CLi (?78°C, molar ratio = 1:1:1) preferrably 2 and (me₃Si)₂P? PCl(Cme₃) are formed, whereas after warming the mixture to 20°C, 4 and (me₃Si)₂P? PH(Cme₃) are found to be the main products. These reactions are induced by the cleavage of 1 by means of me₃CLi, and by the formation of (me₃Si)₂PLi and me₃C? PCl₂.