A fully recyclable heterogenized Cu catalyst for the general carbene transfer reaction in batch and flow

Abstract

Carbene transfer reactions can be performed in batch and flow with a highly active, chemically stable heterogenized tris(triazolyl)methyl copper(i) catalyst.

Catalytic Enantioselective Flow Processes with Solid‐Supported Chiral Catalysts

“…We reasoned that, if the complex was formed from a cationic copper species rather than with CuCl, the chances of leaching would diminish. Consequently, solid‐supported TTM was treated with [Cu(MeCN) 4 ]PF 6 and the resulting cationic complex 28 was benchmarked with the ethyl diazoacetate insertion onto ethanol, in the framework of a collaboration with the group of Díaz‐Requejo and Pérez from the University of Huelva . The system was incredibly robust, allowing for a flow process that spanned 48 h working at flow rates as high as 500 μL min −1 .…”

Synthesis and catalytic applications of C3-symmetric tris(triazolyl)methanol ligands and derivatives

“…Very recently, Díaz-Requejo, Pérez and Pericàs et al 71 reported on the preparation of a fully recyclable heterogenized cationic copper(I) complex 34 and its catalytic performance in carbene transfer reactions 72 The heterogenized system 34 (5.2 mol%) efficiently catalysed a diverse variety of carbene transfer reactions, under neat conditions or in DCM as solvent at rt, by using inexpensive ethyl diazoacetate (40) as the carbene source (Scheme 19). 71 Insertion reactions of the carbene unit into C−H bonds of cyclohexane (35) and tetrahydrofuran (36), the O−H bond of ethanol (37) and the N−H bond of aniline (14a), as well as addition reactions to benzene (38; Büchner reaction) and 1-phenyl-1-propyne (39; cyclopropenation) were all successfully performed giving rise to an array of products (41−46) in very high yields (82 99% yield).…”

“…71 Insertion reactions of the carbene unit into C−H bonds of cyclohexane (35) and tetrahydrofuran (36), the O−H bond of ethanol (37) and the N−H bond of aniline (14a), as well as addition reactions to benzene (38; Büchner reaction) and 1-phenyl-1-propyne (39; cyclopropenation) were all successfully performed giving rise to an array of products (41−46) in very high yields (82 99% yield). After each carbene transfer reaction, the catalyst was readily separated by simple filtration and reused for next cycle.…”

“…To exploit these advantages, the use in flow of immobilised catalyst 34 for carbene transfer reactions from ethyl diazoacetate (40) was implemented. 71 To challenge the catalyst' useful life in flow, the insertion of the carbene derived from 40 into the O−H bond of ethanol (37) was studied by using the affordable experimental setup depicted in Fig. 6.…”

Advances in Organic and Organic-Inorganic Hybrid Polymeric Supports for Catalytic Applications

“…Recently, the polystyrene-linked tris(triazolyl)methanecopper (I) cationic catalyst 162 was reported for the general carbene transfer reaction in batch and flow reactions [103]. It was prepared by reaction between the polystyrene-supported tris(triazolyl) methyl complex 161 and [Cu (MeCN)4][PF6] in dichloromethane at room temperature (Scheme 62).…”