Polymer‐Supported, Carbon Dioxide‐Protected N‐Heterocyclic Carbenes: Synthesis and Application in Organo‐ and Organometallic Catalysis

Abstract

Abstract:The synthesis of a resin-supported, carbon dioxide-protected N-heterocyclic carbene (NHC) and its use in organocatalysis and organometallic catalysis are described. The resin-bound carbon dioxide-protected NHC-based catalyst was prepared via ring-opening metathesis copolymerization of 1,4,4a,5,8,8a-hexahydro-1,4,5,8-exo,endo-dimethanonaphthalene (DMNH6) with 3-(bicycloA C H T U N G T R E N N U N G [2.2.1]hept-5-en-2-ylmethyl)-1-(2-propyl)-3,4,5,6-tetrahydropyrimidin-1-ium-2-carboxylate (M1), using the well-defined Schrock catalyst

Polymers for Green C–C Couplings

“…The reaction of this zwitterionic species with PdCl 2 afforded a catalyst that was used in the Heck reaction with good activity and recyclability without contamination of the products (Ͻ 0.1 ppm of Pd). [71] Figure 3. ROMP of polynorbornene-supported ligands.…”

Transfer Hydrogenation Catalysis by a N‐Heterocyclic Carbene Iridium Complex on a Polyoxometalate Platform

“…4 in CDCl 3 as external references. FT-IR (KBr) spectra were collected on a Thermo Quest Nicolet 5700 instrument.…”

“…[2,3] However, heterogeneous THC by Ir-NHC species is limited to polymeric supports and plagued by irreversible leaching. [4] We present herein a synthetic strategy for the immobilization of Ir-NHC domains on a molecular polyoxometalate (POM), resulting in the vicinal arrangement of two reactive sites (Scheme 1). POMs offer a unique nano-dimensional and totally inorganic platform, and they are often considered as a molecular fragment of metal oxide solid supports (oxides, zeolites, and mesoporous materials).…”

Development of new methods in modern selective organic synthesis: preparation of functionalized molecules with atomic precision

“…256, 257, 274, 277, 292 ± 294 Note also the syntheses by double C7H activation of diaminomethane derivatives (see Scheme 70, pathway d ) 273 and elimination of CO 2 from zwitter-ionic carboxylates (see Scheme 70, pathway e). 295,296 The complexes can be prepared by the oxidative addition of 2-haloamidines (see Scheme 70, pathway f ) 297 and by cyclization of metal-coordinated isonitriles with g-chloro derivatives of secondary amines (Scheme 70, pathway g). 298…”