51370-00-4Relevant academic research and scientific papers
Radical C?H Acylation of Nitrogen Heterocycles Induced by an Aerobic Oxidation of Aldehydes
Paul, Subhasis,Bhakat, Manotosh,Guin, Joyram
supporting information, p. 3154 - 3160 (2019/08/30)
An aerobic radical approach for the synthesis of unsymmetrical heteroaryl ketones is described herein. The reaction involves cross-dehydrogenative coupling between aldehydes and heteroaromatic bases with molecular oxygen (O2). The key aspect of the method is the generation of reactive acyl radical via homolytic activation of aldehyde C?H bond using O2 as the sole oxidant. The reaction has a good substrate scope with respect to aldehydes and functionalized nitrogen heterocycles. Based on our mechanistic studies, a radical chain pathway is suggested for the reaction. A synthetic application of the method is demonstrated in the formal synthesis of natural alkaloid (±) angustureine.
Transition metal-free Minisci reaction promoted by NCS, and TBHP: Acylation of heteroarenes
Siddaraju, Yogesh,Prabhu, Kandikere Ramaiah
supporting information, p. 959 - 967 (2016/02/03)
A method for acylation for heteroarenes under metal-free conditions has been described using NCS as an additive and TBHP as an oxidant. This method has been successfully employed in acylation of a variety of aldehyde with heteroarenes. The application of the method has been illustrated in synthesizing isoquinoline derived natural products. This strategy provides an efficient, mild and inexpensive method for acylation of heteroarenes.
Dioxygen-Mediated Decarbonylative C-H Alkylation of Heteroaromatic Bases with Aldehydes
Paul, Subhasis,Guin, Joyram
supporting information, p. 17618 - 17622 (2015/12/05)
An operationally simple and economical method for the direct alkylation of heteroaromatic bases employing readily available aldehydes as alkyl radical precursors and molecular oxygen as a reagent is presented. This simple transformation demonstrates a broad substrate scope with respect to aldehydes and nitrogen heterocycles, enabling the introduction of several medicinally important yet challenging alkyl moieties, such as ethyl, isopropyl, tert-butyl, and cyclohexyl to the different classes of heterocyclic bases in good to excellent yields. A simple method for the direct alkylation of heteroaromatic bases with aldehydes as inexpensive alkyl radical precursors and molecular oxygen as a reagent is presented. This transformation demonstrates a broad substrate scope with respect to aldehydes and nitrogen heterocycles, enabling the introduction of various alkyl moieties to heterocyclic bases (>40 examples) in good to excellent yields.
Studies on Organometallic Compounds. III. Reaction of Trimethylstannylazines with Acyl Chlorides. A Novel C-C Bond Formation of Pyridine Nuclei
Yamamoto, Yutaka,Yanagi, Akihiko
, p. 2003 - 2010 (2007/10/02)
Introduction of an acyl group at the α-, β-, and γ-positions of pyridine nuclei was accomplished. 2-Trimethylstannyl-pyridine and -quinoline and 1-trimethylstannylisoquinoline directly reacted with various acyl chlorides to give the corresponding 2-pyridyl, 2-quinolyl, and 1-isoquinolyl ketones, respectively.Reaction of 3-trimethylstannylpyridine, -quinoline, and -isoquinoline with acyl chlorides proceeded smoothly under catalysis by PdCl2 or PdCl2(PPh3)2 to afford the corresponding ketones in good yields.Similary, 4-pyridyl, -quinolyl, and -isoquinolyl ketones were prepared from corresponding 4-trimethylstannyl derivatives and acyl chlorides.Keywords--trimethylstannylazine; palladium-catalyzed reaction; acylation; palladium dichloride; dichlorobis(triphenylphosphine)palladium(II)
