Structure Modulated Electronic Contributions to Metalloenediyne Reactivity: Synthesis and Thermal Bergman Cyclization of MLX<sub>2</sub> Compounds
作者:Sibaprasad Bhattacharyya、Aurora E. Clark、Maren Pink、Jeffrey M. Zaleski
DOI:10.1021/ic801116q
日期:2009.5.4
The synthesis of novel metalloendiyne complexes MLRX2 (where L = 1,4-dibenzyl/diethyl-1,4-diaza-cyclododec-8-ene-6,10-diyne, X = halogen) are reported with their X-ray crystal structures and thermal Bergman cyclization temperatures. Two distinct types of constructs are obtained; the Zn(II) compounds are tetrahedral, while the Cu(II) and the Pd(II) compounds are all distorted- or square-planar. Each
新型金属茂金属配合物MLRX 2的合成(其中L = 1,4-二苄基/二乙基-1,4-二氮杂-环十二烷基-8-烯-6,10-二炔,X =卤素)报道了它们的X射线晶体结构和热Bergman环化温度。获得两种不同类型的构建体。Zn(II)化合物为四面体,而Cu(II)和Pd(II)化合物均为扭曲或方形。每个都具有结构相似的烯二炔构象和临界距离(3.75-3.88Å)。固态的四方Cu(II)物种在固态下均表现出Bergman环化温度在140至150°C之间,而方形Pd(II)类似物具有相似的临界距离,但在明显更高的温度(205-220°C)下可环化。相反,Zn(II)衍生物表现出明显的卤素依赖性,其中X = Cl具有最高的Bergman环化温度,X = I的2个化合物显示出最低的Bergman环化温度(144°C),类似于Cu(II)衍生物。而且,对于平面结构,R基团对环化温度的影响很小。但是,对于四面体ZnLX