Transient terminal Cu-nitrene intermediates from discrete dicopper nitrenes
Transient terminal Cu-nitrene intermediates from discrete dicopper nitrenes
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DOI：
10.1021/ja065299l
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发表时间：
2006-11-29
影响因子：
15
通讯作者：
Warren, Timothy H.
中科院分区：
文献类型：
--
作者：
Badiei, Yosra M.;Krishnaswamy, Ammani;Warren, Timothy H.
β-二酮亚胺合铜{[Me 3 NN]Cu}2（μ-甲苯）与芳基叠氮N_3Ar（Ar = 3，5-Me_2C_6H_3）在甲苯中反应，立即重氮化生成双铜氮烯{[Me_3NN]Cu}2（μ-NAr）（2），产率77%。2的X射线结构显示氮烯与两个Cu中心几乎对称成键，两个Cu中心相距2.911（1）沿着，Cu-N距离为1.794（5），Cu-N-Cu夹角为107.8（2）°。该结构在概念上与二铜卡宾{[MexNN]Cu}2（μ-CPh 2）（x= 2或3）（Dai，X.;沃伦·J·阿姆Chem.Soc.2004，126，10085中所述。Badiei，Y. M.; [美]有机金属. Chem.2005，690，5989）。其具有较短的Cu-Cu距离（2.4635（7）或2.485（1）°）和锐角Cu-C-Cu角（79.51（14）或80.1（2）°）。将Cu（I）苯胺亚胺{[Me_2Al]Cu}_2（由CuOtBu和苯胺亚胺H[Me_2Al]以77%的产率制得）加入到2的苯-d_6溶液中，在3 h内生成两种新的苯胺亚胺配合物{[Me_2Al]Cu（μ- NAr）Cu[Me_3NN]（5）和{[Me_2Al]Cu}_2（μ-NAr）（6）以及[Me_3NN]Cu（苯）.这些观察结果与[Me 3 NN]Cu片段从2缓慢解离以产生瞬时末端氮烯[Me 3 NN]CuNAr和[Me 2AI]CuNAr的现象一致，[Me 2AI]Cu片段迅速捕获并形成新的不对称和对称双铜氮烯5和6。初步的反应性研究表明，亲电反应的氮烯部分。二氯硝基苯2与10当量的PMe 3和CNTBu反应，分别以94%和92%的产率得到ArNPMe 3和ArNCNTBu，同时形成[Me 3 NN]Cu（L）（L = PMe 3和CNTBu）。2和2当量PMe 3之间的反应允许观察结构表征的Cu（I）磷酰亚胺[Me 3 NN]Cu（ArNPMe 3）（7）。
Reaction of the copper(I) β-diketiminate {[Me3NN]Cu}2(μ-toluene) with the aryl azide N3Ar (Ar = 3,5-Me2C6H3) in toluene results in immediate effervescence and formation of the dicopper nitrene {[Me3NN]Cu}2(μ-NAr) (2) in 77% yield. The X-ray structure of2shows nearly symmetric bonding of the nitrene to two Cu centers separated by 2.911(1) Å with Cu−N distances of 1.794(5) and 1.808(5) Å along with a Cu−N−Cu angle of 107.8(2)°. This structure is conceptually related to the dicopper carbenes {[MexNN]Cu}2(μ-CPh2) (x= 2 or 3) (Dai, X.; Warren J.Am. Chem. Soc.2004,126, 10085. Badiei, Y. M.; Warren J.Organomet. Chem.2005,690, 5989.) which exhibit shorter Cu−Cu distances (2.4635(7) or 2.485(1) Å) and acute Cu−C−Cu angles (79.51(14) or 80.1(2)°). Addition of the Cu(I) anilidoimine {[Me2AI]Cu}2(prepared from CuOtBu and the aniline-imine H[Me2AI] in 77% yield) to a benzene-d6solution of2results in the formation of two new anilidoimine complexes {[Me2AI]Cu(μ- NAr)Cu[Me3NN] (5) and {[Me2AI]Cu}2(μ-NAr) (6) as well as [Me3NN]Cu(benzene) over 3 h. These observations are consistent with the slow dissociation of a [Me3NN]Cu fragment from2to generate the transient terminal nitrenes [Me3NN]CuNAr and [Me2AI]CuNAr quickly trapped by the [Me2AI]Cu fragment to form the new unsymmetrical and symmetrical dicopper nitrenes5and6. Preliminary reactivity studies indicate electrophilic reactivity at the nitrene moiety. Dicopper nitrene2reacts with 10 equiv PMe3and CNtBu to give ArNPMe3and ArNCNtBu in 94% and 92% yields, respectively, with concomitant formation of [Me3NN]Cu(L) (L = PMe3and CNtBu). Reaction between2and 2 equiv PMe3allows for observation of the structurally characterized Cu(I) phosphaimide [Me3NN]Cu(ArNPMe3) (7).