3678-72-6Relevant articles and documents
Metal-Free Heterogeneous Semiconductor for Visible-Light Photocatalytic Decarboxylation of Carboxylic Acids
Shi, Jiale,Yuan, Tao,Zheng, Meifang,Wang, Xinchen
, p. 3040 - 3047 (2021/03/09)
A suitable protocol for the photocatalytic decarboxylation of carboxylic acids was developed with metal-free ceramic boron carbon nitrides (BCN). With visible light irradiation, BCN oxidize carboxylic acids to give carbon-centered radicals, which were trapped by hydrogen atom donors or employed in the construction of the carbon-carbon bond. In this system, both (hetero)aromatic and aliphatic acids proceed the decarboxylation smoothly, and C-H, C-D, and C-C bonds are formed in moderate to high yields (35 examples, yield up to 93%). Control experiments support a radical process, and isotopic experiments show that methanol is employed as the hydrogen atom donor. Recycle tests and gram-scale reaction elucidate the practicability of the heterogeneous ceramic BCN photoredox system. It provides an alternative to homogeneous catalysts in the valuable carbon radical intermediates formation. Moreover, the metal-free system is also applicable to late-stage functionalization of anti-inflammatory drugs, such as naproxen and ibuprofen, which enrich the chemical toolbox.
Nickel-Catalyzed C(sp3)-H Arylation of Diarylmethane Derivatives with Aryl Fluorides
Li, Jie,Wu, Chen,Zhou, Bihui,Walsh, Patrick J.
, p. 2993 - 2999 (2018/03/09)
A novel nickel-catalyzed C(sp3)-H arylation with nonactivated aryl fluorides is reported. The use of 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene (IMes) as a ligand was found to be critical to the success of the reaction. This new method enables the synthesis of a wide range of triarylmethane derivatives.
Transition-Metal-Free Cross-Coupling of Aryl and N-Heteroaryl Cyanides with Benzylic Zinc Reagents
Quinio, Pauline,Roman, Daniela Sustac,León, Thierry,William, Sharankini,Karaghiosoff, Konstantin,Knochel, Paul
supporting information, p. 4396 - 4399 (2015/09/15)
Functionalized 4-benzylated pyridines can be efficiently prepared by a transition-metal-free cross-coupling between various benzylic zinc chlorides and substituted 4-cyanopyridines in THF/DMPU under microwave irradiation (40 °C, 0.5-1.5 h). Selective benzylations on polycyano-aromatics have also been achieved under these mild conditions. We also report a novel oxidative nucleophilic substitution of a hydrogen on 1,3-dicyanobenzene using benzylic zinc reagents.