A Seven-Membered N,N′-Diamidocarbene
A Seven-Membered N,N′-Diamidocarbene
复制标题
DOI：
10.1021/om1007665
复制
发表时间：
2010-10-25
期刊：
影响因子：
2.8
通讯作者：
Bielawski, Christopher W.
中科院分区：
文献类型：
--
作者：
Hudnall, Todd W.;Tennyson, Andrew G.;Bielawski, Christopher W.
N，N'-二烷基甲脒与邻苯二甲酰氯缩合得到1个中心点HCl，经碱处理得到2,4-二烷基苯并[e][1,3]二氮平-1,5-二酮-2-基二烯(1)，产率高达85%。利用游离DAC合成了四种新的晚期过渡金属配合物：[Rh(cod)(1)Cl] (2a) （cod = 1,5-环二烯）、[Ir(cod)(1)Cl] （2b）、[Rh(CO)(2)(1)Cl] （3a）和[1- aucl](5)。从3a的红外光谱计算得到1的Tolman电子参数（TEP）为2047 cm（-1）。该TEP值比已知的DAC低约10 cm(-1)，比已知的咪唑-2-基烯低5 cm(-1)，表明DAC 1是一个相对强的电子供体。此外，对2a和2b的电化学分析证实了3a的红外数据，发现与n -杂环碳烯负载的类似配合物相比，E-1/2值的阴极位移约为0.16 V。发现金配合物5对苯乙炔的水化反应具有催化作用，在负载2mol %的催化剂下，在80℃下反应12 h，苯乙酮的产率可达78%。用2,6-二甲基苯基异氰化物处理1得到N， N'-二胺酮亚胺4作为热坚固的结晶固体。
Condensation of N,N'-dimesitylformamidine with phthaloyl chloride afforded 1 center dot HCl, which, upon treatment with base, afforded 2,4-dimesitylbenzo[e][1,3]diazepin-1,5-dione-2-ylidene (1), a seven-membered N,N'-diamidocarbene (DAC), in high yield (85%). The free DAC was used to synthesize four new, late transition metal complexes: [Rh(cod)(1)Cl] (2a) (cod = 1,5-cyclooctadiene), [Ir(cod)(1)Cl] (2b), [Rh(CO)(2)(1)Cl] (3a), and [1-AuCl] (5). The Tolman electronic parameter (TEP) of 1 was calculated to be 2047 cm(-1) from the IR spectrum of 3a. This TEP value is approximately 10 cm(-1) than known DACs and 5 cm(-1) lower than known imidazol-2-ylidenes, indicating that DAC 1 is a relatively strong electron donor. Additionally, electrochemical analyses of 2a and 2b corroborated the IR data obtained on 3a and revealed E-1/2 values that were shifted cathodically by ca. 0.16 V when compared to analogous complexes supported by N-heterocyclic carbenes. The gold complex 5 was found to catalyze the hydration of phenylacetylene, affording acetophenone in yields up to 78% after 12 h at 80 C at a catalyst loading of 2 mol %. Treatment of 1 with 2,6-dimethylphenylisocyanide afforded N, N'-diamidoketenimine 4 as a thermally robust, crystalline solid.