Department of Chemistry, University of Toronto, Toronto, ON, Canada.
Chemistry. 2011 Aug 22;17(35):9640-50. doi: 10.1002/chem.201100286.
The reaction of a solution of B(C6F4H)3 and either iPr3P or tBu3P with CO2 afforded the species R3P(CO2)B(C6F4H)3 (R=iPr (1), tBu (2)). In a similar fashion the boranes, RB(C6F5)2 (R=hexyl, cyclohexyl (Cy), norbornyl), ClB(C6F5)2, or PhB(C6F5)2 were combined with tBu3P and CO2 to give the species tBu3P(CO2)BR(C6F5)2 (R=hexyl (3), Cy (4), norbornyl (5), Cl (6), Ph (7)). Similarly, the compounds [tBu3PH][RBH(C6F5)2] (R= hexyl (8), Cy (9), norbornyl (10)) were prepared by reaction of the precursor frustrated Lewis pair (FLP) with H2. Subsequent reactions of 9 and 10 with CO2 afforded the species [((C6F5)2BR)2(μ-HCO2)][tBu3PH] (R= Cy (11), norbornyl (12)). In related chemistry, combinations of the boranes RBG(C6F5)2 (R=hexyl, Cy, norbornyl) with tBu3P treated with an equivalent of formic acid gave [(C6F5)2BR(HCO2)][tBu3PH] (R=hexyl (13), Cy (14), norbornyl (15)). Subsequent addition of an additional equivalent of borane provides a second synthetic route to 11 and 12. Crystallographic studies of compounds 2-6 and 8-14 are reported and discussed. Further understanding of the FLP complexation and activation of CO2 is provided by computational studies.
三异丙基膦（iPr3P）或叔丁基膦（tBu3P）与 B(C6F4H)3 的溶液与 CO2 反应得到了 R3P(CO2)B(C6F4H)3（R=iPr（1），tBu（2））。类似地，硼烷 RB(C6F5)2（R=正己基、环己基（Cy）、降冰片基）、ClB(C6F5)2 或 PhB(C6F5)2 与 tBu3P 和 CO2 结合得到了 tBu3P(CO2)BR(C6F5)2（R=正己基（3）、Cy（4）、降冰片基（5）、Cl（6）、Ph（7））。同样，[tBu3PH][RBH(C6F5)2]（R=正己基（8）、Cy（9）、降冰片基（10））是通过前体受阻路易斯对（FLP）与 H2 的反应制备的。随后，9 和 10 与 CO2 的反应得到了[((C6F5)2BR)2(μ-HCO2)][tBu3PH]（R=Cy（11）、降冰片基（12））。在相关化学中，RBG(C6F5)2（R=正己基、Cy、降冰片基）与 tBu3P 的组合用等当量的甲酸处理得到了[(C6F5)2BR(HCO2)][tBu3PH]（R=正己基（13）、Cy（14）、降冰片基（15））。随后加入另外一当量的硼烷提供了到 11 和 12 的第二种合成途径。报道并讨论了化合物 2-6 和 8-14 的晶体结构研究。计算研究进一步提供了对 FLP 络合和 CO2 活化的理解。
