Metal–Ligand Cooperation on a Diruthenium Platform: Selective Imine Formation through Acceptorless Dehydrogenative Coupling of Alcohols with Amines
作者:Biswajit Saha、S. M. Wahidur Rahaman、Prosenjit Daw、Gargi Sengupta、Jitendra K. Bera
DOI:10.1002/chem.201304403
日期:2014.5.19
complexes, bridged by naphthyridine‐functionalized N‐heterocyclic carbene (NHC) ligands featuring a hydroxy appendage on the naphthyridine unit, are obtained in a single‐pot reaction of [Ru2(CH3COO)2(CO)4] with 1‐benzyl‐3‐(5,7‐dimethyl‐1,8‐naphthyrid‐2‐yl)imidazolium bromide (BIN⋅HBr) or 1‐isopropyl‐3‐(5,7‐dimethyl‐1,8‐naphthyrid‐2‐yl)imidazolium bromide (PIN⋅HBr), TlBF4, and substituted benzaldehyde containing
金属金属单独使用键合的二钌络合物,桥接由萘啶官能化的N-杂环卡宾(NHC)配体为特色的萘啶单元上的羟基的附属物,以[钌的单罐反应,得到2(CH 3 COO)2( CO)4 ]用1-苄基-3-(5,7-二甲基-1,8- naphthyrid -2-基)咪唑鎓溴化物(BIN ⋅的HBr)或1-异丙基-3-(5,7-二甲基-1- ,8-naphthyrid -2-基)咪唑鎓溴化物(PIN ⋅的HBr),TlBF 4,以及含有吸电子基团的取代苯甲醛。修饰的NHC-萘啶-羟基配体跨越了二氢键单元,其中NHC碳和羟基氧占据了轴向位点。在催化量的弱碱1,4-二氮杂双环[2.2.2]辛烷(DABCO)存在下,所有合成的化合物均能催化醇的无受体脱氢成相应的醛。此外,醇与胺的无受体脱氢偶联(ADHC)提供了相应的亚胺作为唯一产物。底物范围用1(BIN,对硝基苯甲醛)检查。相似的络合物[Ru 2(CO)4(CH