330-12-1Relevant articles and documents
Milled Dry Ice as a C1 Source for the Carboxylation of Aryl Halides
O'Brien, Connor J.,Nicewicz, David A.
supporting information, p. 814 - 816 (2021/03/01)
The use of carbon dioxide as a C1 chemical feedstock remains an active field of research. Here we showcase the use of milled dry ice as a method to promote the availability of CO 2in a reaction solution, permitting practical synthesis of arylcarboxylic acids. Notably, the use of milled dry ice produces marked increases in yields relative to those obtained with gaseous CO 2, as previously reported in the literature.
An Anionic, Chelating C(sp3)/NHC ligand from the Combination of an N-heterobicyclic Carbene and Barbituric Heterocycle
Benaissa, Idir,Gajda, Katarzyna,Vendier, Laure,Lugan, No?l,Kajetanowicz, Anna,Grela, Karol,Michelet, Véronique,César, Vincent,Bastin, Stéphanie
supporting information, p. 3223 - 3234 (2021/09/30)
The coordination chemistry of the anionic NHC1-based on an imidazo[1,5-a]pyridin-3-ylidene (IPy) platform substituted at the C5 position by an anionic barbituric heterocycle was studied with d6(Ru(II), Mn(I)) and d8(Pd(II), Rh(I), Ir(I), Au(III)) transition-metal centers. While the anionic barbituric heterocycle is planar in the zwitterionic NHC precursor 1·H, NMR spectroscopic analyses supplemented by X-ray diffraction studies evidenced the chelating behavior of ligand 1-through the carbenic and the malonic carbon atoms in all of the complexes, resulting from a deformation of the lateral barbituric heterocycle. The complexes were obtained by reaction of the free carbene with the appropriate metal precursor, except for the Au(III) complex 10, which was obtained by oxidation of the antecedent gold(I) complex [AuCl(1)]?with PhICl2as an external oxidant. During the course of the process, the kinetic gold(I) intermediate 9 resulting from the oxidation of the malonic carbon of the barbituric moiety was isolated upon crystallization from the reaction mixture. The νCOstretching frequencies recorded for complex [Rh(1)(CO)2] (5) demonstrated the strong donating character of the malonate-C(sp3)/NHC ligand 1-. The ruthenium complex [Ru(1)Cl(p-cymene)] (11) was implemented as a precatalyst in the dehydrogenative synthesis of carboxylic acid derivatives from primary alcohols and exhibited high activities at low catalyst loadings (25-250 ppm) and a large tolerance toward functional groups.
CO2 (De)Activation in Carboxylation Reactions: A Case Study Using Grignard Reagents and Nucleophilic Bases
Valera Lauridsen, Jerik Mathew,Cho, Sung Yeon,Bae, Han Yong,Lee, Ji-Woong
supporting information, p. 1652 - 1657 (2020/03/30)
Carbon dioxide (CO2) is an intrinsically stable molecule. However, its reactivity toward nucleophilic bases has constituted an appealing characteristic for applications such as CO2 capture and functionalization. To shed light on the role of nucleophilic bases in CO2 functionalization, we performed some mechanistic studies using nitrogen-containing bases as an additive-in catalytic amounts-for carboxylation reactions of Grignard reagents. Our kinetic analysis and in situ infrared spectroscopy revealed the role of nucleophilic bases, particularly that of DBU (1,8-diazabicycloundec-7-ene), in CO2 (de)activation for carboxylation reactions.
