CONCERNING THE INFLUENCE OF THE SUBSTITUE NTS R=PH, NET(2), PR-I, AND(T)BU IN TRIPHOSPHANES (R(2)P)(2)P-SIME(3) AND PHOSPHIDES LI(THF)(2)[(R(2)P)(2)P] ON THE FORMATION AND PROPERTIES OF PHOSPHINO-PHOSPHINIDENE-PHOSPHORANES

The triphosphanes X(2)P-P(SiMe(3))-PY2 5, 7, 9, 11, 13 and the derived phosphides Li(THF)(2)[X(2)P-P-PY2] 6, 8, 10, 12, 14 were synthesized: 5 and 6 with X(2) = Pr-i(2) and Y-2 = (i)Bu(2), 7 and 8 with X(2) = Y -2=Ph(i)Bu, 9 and 10 with X(2) = (i)Bu(2) and Y-2=Ph(2), 11 and 12 wit h X(2) = Y-2=Ph(2), and 13 and 14 with X(2) = (i)Bu(2) and Y-2 = (NEt( 2))(2). The silylated triphosphanes at -70 degrees C in toluene with C Br4 may yield X(2)P-P=P(Br)Y-2 and X(2)P-P(Br)-PY2, and the lithiated phosphides with MeCl may yield X(2)P-P=P(Me)Y-2 and X(2)P-P(Me)-PY2 de pending on X and Y. The bromiated product of 5 (X(2) = (i)Prp(2) Y-2 = (t)Bu(2)) is the ylide (Pr2P)-Pr-i-P=P(Br)(t)Bu(2), and the methylate d derivatives of 6 are both (Pr2P)-Pr-i-P=P(Me)(t)Bu(2), (i)Bu(2)P-P=P (Me)Pr-i and the methylated triphosphane. Ph(2)P-P=P(Br)(t)Bu(2) as we ll as the brominated triphosphane are obtained from 9 (X(2) = (t)Bu(2) , Y-2 = Ph(2)), and similarly Ph(2)P-P=P(Me)(i)Bu(2) and the methylate d triphosphane from 10. Compound 14 (X(2) = (i)Bu(2), Y-2 = (NEt(2))(2 ) gives rise to the brominated ylide (i)Bu(2)P-P=P(Br).(NEt(2))(2) and to the brominated triphosphane, and on methylation to (t)Bu(2)P-P=P(M e)(NEt(2))(2) and to (i)Bu(2)P-P(Me)-P .(NEt(2))(2) (main product). Th e Br substituted derivatives decompose already on warming to -30 degre es C, while the methylated compounds are stable up to 20 degrees C.