Click-Connected Ligand Scaffolds: Macrocyclic Chelates for Asymmetric Hydrogenation
摘要:
Click chemistry is used to construct ligand scaffolds for a series of chiral diphosphites. Enantioselectivity as high as 97% ee is obtained using these click ligands in rhodium-catalyzed asymmetric hydrogenation. Control experiments and spectroscopic data suggest that a 16-membered PP-macrocyclic Rh(I) chelate is formed.
A Highly Active Catalyst for Huisgen 1,3-Dipolar Cycloadditions Based on the Tris(triazolyl)methanol−Cu(I) Structure
作者:Salih Özçubukçu、Erhan Ozkal、Ciril Jimeno、Miquel A. Pericàs
DOI:10.1021/ol9018776
日期:2009.10.15
A new tris(1-benzyl-1H-1,2,3-triazol-4-yl)methanol ligand 3 has been prepared by a triple Cu(I)-catalyzed alkyne-azide 1,3-dipolar cycloaddition (CuAAC). Ligand 3 forms a stable complex with CuCl, which catalyzes the Huisgen 1,3-dipolar cycloaddition on water or under neat conditions. Low catalyst loadings, short reaction times at room temperature, and compatibility with free amino groups make 3-CuCl an outstanding catalyst for CuAAC.
Click-Connected Ligand Scaffolds: Macrocyclic Chelates for Asymmetric Hydrogenation
作者:Qing Zhang、James M. Takacs
DOI:10.1021/ol702890s
日期:2008.2.1
Click chemistry is used to construct ligand scaffolds for a series of chiral diphosphites. Enantioselectivity as high as 97% ee is obtained using these click ligands in rhodium-catalyzed asymmetric hydrogenation. Control experiments and spectroscopic data suggest that a 16-membered PP-macrocyclic Rh(I) chelate is formed.
Fine-Tunable Tris(triazolyl)methane Ligands for Copper(I)- Catalyzed Azide-Alkyne Cycloaddition Reactions
作者:Erhan Ozkal、Patricia Llanes、Fernando Bravo、Alessandro Ferrali、Miquel A. Pericàs
DOI:10.1002/adsc.201300887
日期:2014.3.10
modular tris(triazolyl)methaneligands for copper‐catalyzedazide–alkynecycloaddition (CuAAC) reactions is reported. The synthesis of the first generation ligand, tris(1‐benzyl‐1H‐1,2,3‐triazol‐4‐yl)methanol (1a), suitable for work in aqueous systems, is reported at the 50–100 mmol scale through a one‐stage, environmentally benign procedure. One‐stage procedures for the synthesis of tris(aryltriazolyl)methanol
据报道,已经准备了一个小的模块式三(三唑基)甲烷配体库,用于铜催化的叠氮化物-炔烃环加成反应(CuAAC)。据报道,适用于水性体系的第一代配体,三(1-苄基-1 H -1,1,2,3-三唑-4-基)甲醇(1a)的合成规模为50-100 mmol通过一个阶段性的,对环境无害的程序。设计用于电子微调催化性能和1a衍生醚2c的三(芳基三唑基)甲醇结构(1b,苯基; 1c,对三氟甲基苯基; 1d,对甲氧基苯基)的一步合成程序还报道了设计用于有机溶剂中的CuAAC反应的(OBn)和2d(OMe)。已在六种不同溶剂(水,己烷,甲苯,二氯甲烷,四氢呋喃和乙腈)中苯乙炔与苄基叠氮化物的反应中测试了整套配体(1a–d,2c–d),并进行了鉴定的1B,1C和2C的配位体描绘的最高耐受所考虑的家庭内的溶剂的极性的变化。配体1b–d和2c在小系列炔烃与叠氮化物在两种截然不同的反应介质中环加成反应中的比较性能(1:1)已经研究了叔丁基/