(Trimethylsilyl)phosphine as a Versatile Reagent for Syntheses of New 4-Sila- and 4-Phosphaphosphorinanes.
(Trimethylsilyl)phosphine (Me(3)SiPH(2)) undergoes radical P-H bond addition to vinylphosphines and -silanes to form new 4-phospha- and 4-silaphosphorinanes [vinyl reagent]: [PhP(CH=CH(2))(2)], PhP(C(2)H(4))(2)PSiMe(3) diastereomers (9A/9B); [Et(2)NP(CH=CH(2))(2)], Et(2)NP(C(2)H(4))(2)PSiMe(3) (11); [Me(2)Si(CH=CH(2))(2)], Me(2)Si(C(2)H(4))(2)PSiMe(3) (14); [Si(CH=CH(2))(4)], (CH=CH(2))(2)Si(C(2)H(4))(2)PSiMe(3) (16) and [Me(3)SiP(C(2)H(4))(2)](2)Si (17). Reactions are accompanied by formation of only small quantities of the Markovnikov addition product phospholanes. Methanolysis of the new silylphosphines yields PhP(C(2)H(4))(2)PH diastereomers (10A/10B), Me(2)Si(C(2)H(4))PH (15), (CH=CH(2))(2)Si(C(2)H(4))(2)PH (18), and [HP(C(2)H(4))(2)](2)Si (19). Stepwise methanolysis of 11 yields the phosphorinanes Et(2)NP(C(2)H(4))(2)PH (12) and MeOP(C(2)H(4))(2)PH (13). Oxidation of 15 and 14 with O(2) or O(2)/H(2)O, respectively, yields the phosphine oxide Me(2)Si(C(2)H(4))(2)P(O)H (20) and the phosphinic acid Me(2)Si(C(2)H(4))(2)P(O)OH (21). New compounds were characterized by spectral ((31)P, (1)H, and (13)C NMR, IR, and MS) data. 21 was further characterized by a single-crystal X-ray analysis: monoclinic, P2(1)/c, a = 10.416(2) Å, b = 6.817(1) Å, c = 14.237(3) Å, beta = 106.32(2) degrees, Z = 4, V = 970.3(3) Å(3). The ring of 21 adopts a chair conformation with the P=O bond in an equatorial position. From spectral data, tentative isomeric and conformational structural assignments are made for the new phosphorinanes in solution.
Hackney
Michael L. J.
ML
Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215.
Schubert
David M.
DM
Brandt
Paul F.
PF
Haltiwanger
R. C.
RC
Norman
Arlan D.
AD