The reaction of tBu(C6H4O2)P, with the borane B(C6F5)3 gives rise to NMR data consistent with the formation of the classical Lewis acid–base adduct tBu(C6H4O2)P(B(C6F5)3) (1). In contrast, the NMR data for the corresponding reactions of tBu(C20H12O2)P and Cl(C20H12O2)P with B(C6F5)3 were consistent with the presence of equilibria between free phosphine and borane and the corresponding adducts. Nonetheless, in each case, the adducts tBu(C20H12O2)P(B(C6F5)3) (2) and Cl(C20H12O2)P(B(C6F5)3) (3) were isolable. The species 1 reacts with PhCCH to give the new species tBu(C6H4O2)P(Ph)CCHB(C6F5)3 (4) in near quantitative yield. In an analogous fashion, the addition of PhCCH to solutions of the phosphinestBu(C20H12O2)P, tBuPCl2 and (C6H3(2,4-tBu2)O)3P each with an equivalent of B(C6F5)3 gave rise to L(Ph)CCHB(C6F5)3 (L = tBu(C20H12O2)P5, tBuPCl26 and (C6H3(2,4-tBu2)O)3P 7). X-Ray data for 1, 2, 6 and 7 are presented. The implications of these findings are considered.
tBu(
C6H4O2)P 与
硼烷 B(
C6F5)3 反应产生的核磁共振数据与经典的
路易斯酸碱加合物 tBu( )P(B( )3) 的形成一致 (1)。相反,tBu(
C20H12O2)P 和 Cl( )P 与 B( )3 的相应反应的核磁共振数据则与游离膦和
硼烷与相应加合物之间存在平衡一致。不过,在每种情况下,加合物 tBu( )P(B( )3) (2) 和 Cl( )P(B( )3) (3) 都是可以分离的。物种 1 与 PhCCH 反应生成新物种 tBu( )P(Ph)C
CHB( )3(4),产量接近定量。以类似的方式,将 PhCCH 加入到膦化物 Bu( )P、tBuPCl2 和 (
C6H3(2,4-tBu2)O)3P 的溶液中,每种膦化物都含有等量的 B( )3,从而得到 L(Ph)C
CHB( )3 (L = tBu( )P5、tBuPCl26 和 ( (2,4-tBu2)O)3P 7)。文中给出了 1、2、6 和 7 的 X 射线数据。研究还探讨了这些发现的意义。