Carbon dioxide is a nontoxic, renewable, and abundant C source, whereas C-H bond functionalization represents one of the most important approaches to the construction of carbon-carbon bonds and carbon-heteroatom bonds in an atom- and step-economical manner. Combining the chemical transformation of CO with C-H bond functionalization is of great importance in the synthesis of carboxylic acids and their derivatives. The contents of this Review are organized according to the type of C-H bond involved in carboxylation. The primary types of C-H bonds are as follows: C(sp)-H bonds of terminal alkynes, C(sp )-H bonds of (hetero)arenes, vinylic C(sp )-H bonds, the ipso-C(sp )-H bonds of the diazo group, aldehyde C(sp )-H bonds, α-C(sp )-H bonds of the carbonyl group, γ-C(sp )-H bonds of the carbonyl group, C(sp )-H bonds adjacent to nitrogen atoms, C(sp )-H bonds of o-alkyl phenyl ketones, allylic C(sp )-H bonds, C(sp )-H bonds of methane, and C(sp )-H bonds of halogenated aliphatic hydrocarbons. In addition, multicomponent reactions, tandem reactions, and key theoretical studies related to the carboxylation of C-H bonds are briefly summarized. Transition-metal-free, organocatalytic, electrochemical, and light-driven methods are highlighted.
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http://dx.doi.org/10.1002/cssc.201802012 | DOI Listing |
Org Lett
January 2025
Phostdoctoral Research Base, School of Chemistry and Chemical Engineering, Henan Institute of Science and Technology, Xinxiang, Henan Province 453003, China.
We have developed a novel strategy for decarboxylative radical addition reactions that employs ground-state reduced nicotinamide adenine dinucleotide (NADH) analogues under ambient and open-air conditions, facilitating the efficient formation of Csp-Csp bonds in a variety of substrates. This protocol is distinguished by its operational simplicity, mild reaction conditions, high efficiency, and the use of cost-effective starting materials. Furthermore, experimental studies have provided valuable insights into the reaction mechanism, elucidating the light-independent pathways that promote these transformations.
View Article and Find Full Text PDFOrg Lett
January 2025
Organic Chemistry Department, Faculty of Science, Autonomous University of Madrid, 28049 Madrid, Spain.
The functionalization of the C-N bond of amines is a straightforward strategy for the construction of complex scaffolds or for the late-stage functionalization of pharmaceuticals. Herein, we describe a photoredox-catalyzed strategy for the deaminative alkylation of primary amine-derived isonitriles that provides unnatural amino acid derivatives under mild conditions. The use of silacarboxylic acids as silyl radical precursors enables the generation of carbon-centered radicals that allow the construction of Csp-Csp bonds via a Giese-type addition, avoiding the undesired hydrodeamination product.
View Article and Find Full Text PDFJ Sep Sci
December 2024
College of Chemistry and Chemical Engineering, Yunnan Normal University, Kunming, China.
Chiral macrocycles have emerged as attractive media for chromatographic enantioseparation due to their excellent host-guest recognition properties. In this study, a new chiral stationary phase (CSP) based on 1,1'-binaphthyl chiral polyimine macrocycle (CPM) was reported. The CPM was synthesized by one-step aldehyde-amine condensation of (S)-2,2'-dihydroxy-[1,1'-binaphthalene]-3,3'-dicarboxaldehyde with 1,2-phenylenediamine and bonded on thiolated silica via the thiol-ene click reaction to afford the CSP.
View Article and Find Full Text PDFBMC Oral Health
December 2024
Department of Fixed Prosthodontics, Faculty of Dentistry, Mansoura University, Mansoura, Dakahlia Governorate, Egypt.
Background: The objective of this study was to investigate the effect of bonded substrate, zirconia surface conditioning and the interaction between them on the shear bond strength of monolithic zirconia.
Methods: Forty-eight monolithic zirconia discs were CAD-CAM fabricated and divided into two groups according to surface treatment either as milled and universal primer application (Monobond N, Ivoclar-Vivadent) (P) or sandblasting then universal primer application (Monobond N) (SP). Each main group was further divided into three test groups according to the bonded substrate: dentin (DSP, DP), composite (CSP, CP) or resin modified glass ionomer (RMGI) (GSP, GP).
Inorg Chem
December 2024
Department of Chemistry, Shahid Beheshti University, Tehran 19839-69411, Iran.
This study investigates possible pathways arising from the reaction of anionic K[Pt(C^N)(-MeCH)(CN)] complexes, C^N = 2-phenylpyridinate (ppy) and 7,8-benzo[h]quinolate (bzq), with trifluoroacetic acid (TFA), which has been employed in both experimental and computational approaches. Experimental studies clarify that the products of the protonolysis reaction can vary in the K[Pt(C^N)(-MeCH)(CN)] complex depending on the type of the cyclometalated ligand. In the cyclometalated complex with ppy, only one product was observed, resulting from the cleavage of the Pt-C bond of the cyclometalated ligand.
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