Wehmschulte Rudolf J., Power Philip P.
Department of Chemistry, University of California, Davis, California 95616.
Inorg Chem. 1998 May 4;37(9):2106-2109. doi: 10.1021/ic971442n.
The reaction of (MesAlH(2))(2) (Mes = -C(6)H(2)-2,4,6-t-Bu(3)) with HN(SiMe(3))(2) affords the monomeric amidoarylalane MesAl(H)N(SiMe(3))(2), 1. This product can also be synthesized by the reaction of MesAlH(2) with LiN(SiMe(3))(2), which, in addition, yields the byproducts LiAlH(2){N(SiMe(3))(2)}(2), 3, and MesH. Thermolysis of 1 at 175-180 degrees C affords three different the related and the imide MesAlN(SiMe(3))(), 5. In addition, the previously reported monomeric alane Mes(2)AlH was synthesized in ca. 70% yield by a one-pot reaction between LiMes (generated in situ) and AlH(3).NMe(3). All products were spectroscopically characterized, and the structure of 1 was determined by X-ray crystallography. The Al-N distance (1.819(2) Å) in 1 is relatively long. However, it has a substantial, 18.5 kcal mol(-)(1), Al-N rotation barrier which is attributed to steric congestion rather than Al-N pi bonding.
（MesAlH(2))(2)（Mes = -C(6)H(2)-2,4,6-t-Bu(3)）与HN(SiMe(3))(2)反应生成单体氨基芳基铝烷MesAl(H)N(SiMe(3))(2)，即化合物1。该产物也可通过MesAlH(2)与LiN(SiMe(3))(2)反应合成，此外，还会生成副产物LiAlH(2){N(SiMe(3))(2)}(2)，即化合物3，以及MesH。在175 - 180℃下对1进行热解得到三种不同的相关产物和酰亚胺MesAlN(SiMe(3))（化合物5）。此外，通过LiMes（原位生成）与AlH(3).NMe(3)的一锅法反应，以约70%的产率合成了先前报道的单体铝烷Mes(2)AlH。所有产物均通过光谱进行了表征，化合物1的结构通过X射线晶体学确定。化合物1中Al - N键长（1.819(2) Å）相对较长。然而，它具有高达18.5 kcal mol(-)(1)的Al - N旋转势垒，这归因于空间位阻而非Al - N π键。
