Synthesis and Structure of E-2-(2,4,6-tri tert butylphenylphosphinyl)-2-〔N-(tert-butyldimethylsilyl)-N-(p-chrolophenyl)〕amino-1-(2,4,6-tri tert-butyl-phenyl)phosphacthylene

1　INTRODUCTIONItwaswellknown thatelementsofthesecondary and higherrow are in generaldifficulty to form multiplebondsin which apπ hybridized stateisinvolved〔1〕.Thus,simple compounds containing multiple phosphorus carbon bonds,such as methyl dynephosphine( HC≡P) 〔2 - 3〕 and methylenephosphine( H2 C=PH〔4〕,are notstableat room temperature.Three methods to stabilize compounds containing double ormultiple bond involving phosphorusatom in the pπ hybridized state are often used.The f…

Synthesis and Structure of E-2-(2,4,6-tri tert butylphenylphosphinyl)-2-〔N-(tert-butyldimethylsilyl)-N-(p-chrolophenyl)〕amino-1-(2,4,6-tri tert-butyl-phenyl)phosphacthylene

The title compound E 2 (2,4,6 tri tert butylphenylphosphinyl) 2 〔 N (ter t butyldimethylsilyl) N (p chrolophenyl)〕amino 1 (2,4,6 tri tert butyl phenyl)phosphacthylene(C 49 H 78 NClP 2Si, M r =806.65) was synthesized and characterized by X ray diffraction analysis. The crystal is monoclinic, space group P2 1/n with a=10.319(3), b=23.309(5), c=21.41(1) , β=99.64(5)°, V=5078(3) 3, Z=4, D c =1.05g/cm 3, F(000)=1760, μ =1.92cm -1 . Due to the steric hindrance from substituents around phosphaethylene, the P=C bond length is significantly longer than those observed in its analogues. The values of the three bond angles involved in the sp 2 hybridized carbon atom (C(1)) of the phosphaethylene are 133.4, 115.1 and 111.4° respectively, deviating significantly from the ideal value of 120°. In addition, although 5 sp 2 hybridized atoms (C(2), P(1), C(1), N and C(44)) are sequentially bonded in this molecule, no interaction is observed among the remaining pz orbits of these atoms on the string.