在空间上拥挤的伯烷(Ar Pr i 8 AlH 2)2(Ar Pr i 8 = C 6 H-2,6(C 6 H 2 -2,4,6-Pr i 3)2 -3的反应,描述了具有炔烃和烯烃的5-Pr i 2)。结果表明,末端炔烃HCCSiMe 3和HCCPh的氢化铝在温和条件下容易通过顺式发生-在CC三键上加成Al-H部分,没有消除氢的迹象。在一系列末端烯烃中也观察到了氢铝化反应,但是与内部烯烃或炔烃未观察到反应性。(Ar Pr i 8 AlH 2)2的较高反应性归因于大三联苯取代基的空间拥挤,这有利于铝烷的离解并增加了单体中更具反应性的三配位铝位点的可用性。按照这种观点,研究了三种主要丙氨酸(Ar Pr i 8 AlH 2)2(Ar Pr i 4AlH 2)2(Ar Pr i 4 = C 6 H 3 -2,6(C 6 H 3 -2,6-Pr i 2)2)和(Ar Me 6 AlH 2)2(Ar Me
Synthesis and Characterization of Primary Aluminum Parent Amides and Phosphides
摘要:
The synthesis and characterization. of the sterically crowded primary alanes (Ar(IP+)AIH(2)), (A(iPr) = C6H3-2,6(C6H3-2,6(2)(iPr))(2)) and (A(riPr)A(1)H(2))(2) (A(iPr)' = C6H-2,6(C(6)H(2)2,4,6-(iPr)6)(2)-3,5-(iPr)2) are described. They, along with their previously reported less-hindered analogue (A(iPr)6A(1)H(2))(2) (Arm ea. = C6H3-2,6(C6H2-2,4,6-Me3)2), were reacted with ammonia to give the parent amido alanes {A(iPr)Al(H)NH2}(2) (Arx = A(iPr), 1; A(iPr), 2; A(iPr), 3), which are the first well-characterized hydride amido derivatives of aluminum and are relatively rare examples of parent aluminum amides. In contrast, the reaction of (A(6)(iPr)A(1)H(2))(2) with phosphine yielded the structurally unique Al/P cage species {(A(iPr)A(1))(3)(it-PH2)3(p-PH)PH2} (4) major product and a smaller amount of {(A(6)(iPr)A(1))(4)(mu PH2)4(mu-pH)} (5) as a minor product. All compounds were characterized by NMR and IR spectroscopy, while compounds 2-5 were also characterized by X-ray crystallography.