School of Chemistry, The University of New South Wales, Kensington, Sydney, NSW 2052, Australia.
Dalton Trans. 2013 Oct 21;42(39):14298-308. doi: 10.1039/c3dt51440d.
A series of new cationic Rh(I), Rh(III) and Ir(III) complexes containing hybrid bidentate N-heterocyclic carbene–1,2,3-triazolyl donor of general formulae [Rh(CaT)(COD)]BPh4 (2a–d), [Rh(CaT)(CO)2]BPh4 (3a–d) and [M(CaT)(Cp*)Cl]BPh4 (M = Rh, 4a–d; M = Ir, 5a–c), where CaT = bidentate N-heterocyclic carbene–triazolyl ligands, COD = 1,5-cyclooctadiene and Cp* = 1,2,3,4,5-pentamethylcyclopentadienyl, were synthesised. The imidazolium–1,2,3-triazolyl pre-ligands (1a–c and 1e–i) were readily prepared using the Cu(I) catalysed ‘click reaction’ between phenyl azide or benzyl azides with propargyl functionalised imidazolium salts. The single crystal solid state structures of complexes 2a–d; 3a–b; 4a–d and 5a–b confirm the bidentate coordination of the NHC–1,2,3-triazolyl ligand with the NHC coordinating via the ‘normal’ C2-carbon and the 1,2,3-triazolyl donor coordinating via the N3′ atom to form six membered metallocycles. These complexes are the first examples of Rh and Ir complexes containing the hybrid NHC–1,2,3-triazolyl ligands which exhibit a bidentate coordination mode. A number of these complexes showed limited efficiency as catalysts for the intramolecular hydroamination of 4-pentyn-1-amine to 2-methylpyrroline.
一系列新型的含混合双齿 N-杂环卡宾-1,2,3-三唑供体的 Rh(I)、Rh(III)和 Ir(III) 配合物，通式为 [Rh(CaT)(COD)]BPh4（2a-d）、[Rh(CaT)(CO)2]BPh4（3a-d）和 [M(CaT)(Cp*)Cl]BPh4（M = Rh，4a-d；M = Ir，5a-c），其中 CaT 为双齿 N-杂环卡宾-三唑配体，COD = 1,5-环辛二烯，Cp* = 1,2,3,4,5-五甲基环戊二烯基，被合成了。作为前配体的咪唑鎓-1,2,3-三唑（1a-c 和 1e-i）可以通过 Cu(I)催化的苯甲脒或苄基脒与炔丙基功能化的咪唑鎓盐之间的“点击反应”很容易地制备。配合物 2a-d；3a-b；4a-d 和 5a-b 的单晶固体结构证实了 NHC-1,2,3-三唑配体的双齿配位，其中 NHC 通过“正常”C2-碳配位，1,2,3-三唑供体通过 N3′原子配位，形成六元金属环。这些配合物是首例含有混合 NHC-1,2,3-三唑配体的 Rh 和 Ir 配合物，它们表现出双齿配位模式。这些配合物中的一些在 4-戊炔-1-胺的分子内氨化反应生成 2-甲基吡咯啉的反应中表现出有限的催化效率。
