New copper(I) and silver(I) triazolato-complexes: Synthesis, reactivity and catalytic activity in olefin cyclopropanation
作者:G. Attilio Ardizzoia、Stefano Brenna、Fulvio Castelli、Simona Galli、Chiara Marelli、Angelo Maspero
DOI:10.1016/j.jorganchem.2008.02.014
日期:2008.5
reaction of 1 with ethyl diazoacetate (EDA) in CH2Cl2 afforded a mono-carbene product, as established by 13C NMR data. Finally, the copper derivative 1 proved to be a highly diastereoselective catalyst in olefin cyclopropanation in the presence of ethyl diazoacetate. In the case of internal alkenes a trans:cis ratio of up to 97:3 was reached. The X-ray structure of a dinuclear Ag(I) complex, namely [Ag(H2L1)(PPh3)]2
制备了由3,5-二氨基-1,2,4-三唑与水杨醛(H 3 L 1)和邻-茴香醛(H 3 L 2)等摩尔缩合得到的新型偶氮酸酯配体。这些物种以其阴离子形式,在与Cu(I)和Ag(I)配位时起桥联部分的作用,从而导致以典型的N,N'-明显构象与配体形成双核络合物。铜衍生物[Cu(H 2 L 1)(CH 3 CN)] 2(1)在不稳定的乙腈分子的替换中显示出有吸引力的反应性。特别地,可以通过用一氧化碳取代腈来分离双核铜(I)-羰基配合物[Cu(H 2 L 1)(CO)] 2(4)。此外,通过13 C NMR数据确定,1与重氮乙酸乙酯(EDA)在CH 2 Cl 2中的反应产生了单卡宾产物。最后,在重氮乙酸乙酯的存在下,铜衍生物1在烯烃环丙烷化中被证明是高度非对映选择性催化剂。如果是内部烯烃,则反式为:顺式比例高达97:3。双核Ag(I)配合物,即[Ag(H 2 L 1)(PPh 3)] 2(3)的X射线结构,是通过使聚合的[Ag(H