Preparation and properties of bulky secondary phosphines

Abstract

Received July 14, 1982 The isoelectronic bulky secondary phosphines [(Me3Si)2CH]2PH (1) and [(Me3Si)2N]2PH (3) have been prepared by LiA1H4 reduction of the corresponding chlorides. Compound 1 can also be prepared by treatment of the phosphinyl radical [((Me,Si2)2CH)2P]. (2 ) with C6H5SH. Reduction of the iminophosphine (Me3Si)2NP=N(SiMe3) (4) with LiAlH4 followed by hydrolysis affords (Me,Si),NP(H)N(H)(SiMe,) (5). Compounds 1 and 3 fail to undergo the usual deprotonation reactions; however, 5 undergoes facile deprotonation of the N-H bond to afford the corresponding iminophosphoranide anion [(Me3Si)2N(Me3SiN=)PH](8). Anion 8 also results from the addition of Hto 4. The secondary phosphine 1 undergoes quatemization with Me1 to produce the phosphonium salt [((Me3Si)2CH)2P(Me)H]CI(10). The reaction of 1 with F%(C0)9 and CO~(CO)~ yields the complexes [(Me3Si)2CH]2P(H)Fe(CO)4 (1 1) and [(Me3Si)2CH]2P(H)Co2(C0)7 (12), respectively. NMR data have been acquired for the new compounds presented in this work.