Substitution of labile triflate in [(triphos)Re(CO)2(OTf)]: a new synthetic route to mononuclear and dinuclear ReI complexes
作者:Paola Bergamini、Fabrizia Fabrizi DeBiani、Lorenza Marvelli、Nicoletta Mascellani、Maurizio Peruzzini、Roberto Rossi、Piero Zanello
DOI:10.1039/a806683c
日期:——
New synthetic routes to the neutral complex [(triphos)Re(CO)2(OTf)] [triphos=MeC(CH2PPh2)3, OTf=CF3SO3-] (3) are reported. The triflate ligand in 3 is labile and can be easily replaced by different halides and pseudohalides (CN-, N3-, SCN-, SeCN-, OCN-) to give new mononuclear octahedral ReI complexes of formula [(triphos)Re(CO)2(X)] (X=Cl-, Br-, I-, CN-, N3-, SCN-, SeCN-, OCN-). In some cases, when a double proportion of 3 is treated with the appropriate pseudohalide, rare examples of binuclear ReI complexes featuring a single bridging pseudohalide ligand, [(triphos)Re(CO)2}2(µ-X)]Y (X=CN-, N3-, SCN-, SeCN-; Y=OTf, BPh4-), have been obtained. All of the new ReI complexes have been characterized by conventional spectroscopic methods and by electrochemical and spectroelectrochemical techniques. Selected examples of regioselective electrophilic alkylations of both halide and pseudohalide ligands are also reported. Noticeably, selective methylation of [(triphos)Re(CO)2(η1-X-XCN)] (X=S, Se) affords the complexes [(triphos)Re(CO)2η1-X-X(Me)(CN)}]OTf, which contain the unprecedented methylsulfocyanate and methylselenocyanate ligands.
报道了一种新合成路线用于制备中性配合物[(triphos)Re(CO)2(OTf)] [triphos=MeC(CH2PPh2)3, OTf=CF3SO3-](3)。在3中,三氟甲磺酸配体是易位的,可以被不同的卤素和伪卤素(CN-、N3-、SCN-、SeCN-、OCN-)轻易替代,从而生成新的单核八面体ReI配合物,其化学式为[(triphos)Re(CO)2(X)](X=Cl-、Br-、I-、CN-、N3-、SCN-、SeCN-、OCN-)。在某些情况下,当用适当的伪卤素处理双倍比例的3时,获得了少见的双核ReI配合物,其中以单个桥联伪卤素配体为特征,[(triphos)Re(CO)2}2(µ-X)]Y(X=CN-、N3-、SCN-、SeCN-;Y=OTf、BPh4-)。所有新合成的ReI配合物均已通过常规光谱方法以及电化学和光谱电化学技术进行了表征。此外,报道了一些卤素和伪卤素配体的区域选择性亲电烷基化的精选例子。值得注意的是,对[(triphos)Re(CO)2(η1-X-XCN)](X=S、Se)的选择性甲基化生成的配合物[(triphos)Re(CO)2η1-X-X(Me)(CN)}]OTf,包含了前所未有的甲基硫氰酸盐和甲基硒氰酸盐配体。