6443-69-2Relevant articles and documents
Direct Hydrodecarboxylation of Aliphatic Carboxylic Acids: Metal- and Light-Free
Burns, David J.,Lee, Ai-Lan,McLean, Euan B.,Mooney, David T.
supporting information, p. 686 - 691 (2022/01/28)
A mild and inexpensive method for direct hydrodecarboxylation of aliphatic carboxylic acids has been developed. The reaction does not require metals, light, or catalysts, rendering the protocol operationally simple, easy to scale, and more sustainable. Crucially, no additional H atom source is required in most cases, while a broad substrate scope and functional group tolerance are observed.
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.
Ni-Catalyzed Iterative Alkyl Transfer from Nitrogen Enabled by the in Situ Methylation of Tertiary Amines
Nwachukwu, Chideraa Iheanyi,McFadden, Timothy Patrick,Roberts, Andrew George
, p. 9979 - 9992 (2020/09/03)
Current methods to achieve transition-metal-catalyzed alkyl carbon-nitrogen (C-N) bond cleavage require the preformation of ammonium, pyridinium, or sulfonamide derivatives from the corresponding alkyl amines. These activated substrates permit C-N bond cleavage, and their resultant intermediates can be intercepted to affect carbon-carbon bond-forming transforms. Here, we report the combination of in situ amine methylation and Ni-catalyzed benzalkyl C-N bond cleavage under reductive conditions. This method permits iterative alkyl group transfer from tertiary amines and demonstrates a deaminative strategy for the construction of Csp3-Csp3 bonds. We demonstrate PO(OMe)3 (trimethylphosphate) to be a Ni-compatible methylation reagent for the in situ conversion of trialkyl amines into tetraalkylammonium salts. Single, double, and triple benzalkyl group transfers can all be achieved from the appropriately substituted tertiary amines. Transformations developed herein proceed via recurring events: The in situ methylation of tertiary amines by PO(OMe)3, Ni-catalyzed C-N bond cleavage, and concurrent Csp3-Csp3 bond formation.