SILYLPHOSPHINE - ALKENE REACTION ROUTES TO ACYCLIC AND CYCLIC ORGANOPHOSPHINES

Radical reactions of Me3SiPH2, (Me3Si)(2)PH, Me2Si(PH2)(2) and PH3 wit h selected alkenes have been examined as routes to new organo(silyl)ph osphines. The Me3SiPH2/1,5-hexadiene reaction initiated by AIBN yields the phosphepane Me3SiP(CH2)(6) (11a) and acyclic Me3SiP[(CH2)(4)CH=CH 2](2) (12); the Me3SiPH2/1,3-butadiene reaction yields only acyclic bu tenyl phosphines Me3SiP(H)C4H7 (14A-C) and Me3SiP(C4H7)(2) (15A-D). Re actions of Me3SiPH2 with P(CH=CH2)(3) and MeSi(CH=CH2)(3) yield the vi nyl-substituted cis- and trans-phosphorinanes (CH2=CH)P(C2H4)(2)PSiMe3 (18A/18B) and Me(CH2=CH)Si(C2H4)(2)PSiMe3 (20A/20B). (Me3Si)(2)PH/Me2 Si(CH=CH2)(2) reaction produces only the acyclic (CH2=CH)Me2SiC2H4P(Si Me3)(2) (22) and Me2Si[C2H4P(SiMe3)(2)](2) (25). The Me2Si(PH2)(2)/1,4 -pentadiene reaction yields phosphorinanyl derivatives Me2Si(PH2)[P(CH 2)(5)] (27) and Me2Si[P(CH2)(5)](2) (28); no large-ring products form. The AIBN initiated reaction of CH2=CHCH2PH2 has been reinvestigated; the known bicyclic [(CH2)(3)](2)P-2 is obtained instead of the previou sly reported tricyclic [(Ch(2))(3)](3)P-2. The PH3/Me2Si(CH=CH2)(2) re action yields mixtures of tentatively characterized Me2Si(C2H4)(2)PC2H 4SiMe2(CH=CH2) (29) and [Me2Si(C2H4)(2)PC2H4](2)SiMe2 (30) Solvolysis (with MeOH or H2O) of silylphosphines 11a, 27 (or 28), 12, 14A-C, 15A- D, 18A/18B, 20A/20B, 22 and 25 yields phosphorinanes (CH2)(5)PH (7) an d Me2Si(C2H4)(2)PH (9), the new phosphepane (CH2)(6)PH (11b), HP[(CH2) (4)CH=CH2](2) (13), H2PC4H7 (16A-C), HP(C4H7)(2) (17A-D), the cis- and trans-(CH2=CH)P(C2H4)(2)PH (19A/19B) and Me(CH2=CH)Si(C2H4)(2)PH (21A /21B), (CH2=CH)Me2SiC2H4P(H)SiMe3 (23), (CH2=CH)Me2SiC2H4PH2 (24) and Me2Si(C2H4PH2)(2) (26), Attempts to obtain new tricyclic or large-ring cyclic phosphines by radical ring closure of 19A/19B and 21A/21B or c yclooligomerization of 23 or 24 were unsuccessful. New compounds are c haracterized by spectral (H-1, C-13, and P-31 NMR, MS and IR) data.