20280-86-8Relevant academic research and scientific papers
Visible-Light-Induced Regioselective Deaminative Alkylation of Coumarins via Photoredox Catalysis
Tao, Maoling,Wang, An-Jun,Guo, Peng,Li, Weipiao,Zhao, Liang,Tong, Jie,Wang, Haoyang,Yu, Yanbo,He, Chun-Yang
, p. 24 - 29 (2021/10/19)
3-Alkylated coumarins have many applications in medicinal chemistry, however, methods access to such structures are still limited. Herein, we report a site-selective photocatalytic deaminative alkylation of coumarins utilizing pyridinium-activated aliphatic primary amines as alkylation reagents. The protocol was highlighted by its mild reaction conditions, operational simplicity, and broad functional group compatibility. Moreover, this strategy enables late-stage modification of some pharmaceuticals and natural products, thus providing an appealing approach to valuable molecules in medicinal chemistry. (Figure presented.).
Visible-light promoted oxidative cyclization of cinnamic acid derivatives using xanthone as the photocatalyst
Zhao, Bin,Xu, Bo
, p. 568 - 573 (2021/02/06)
We have developed an efficient photocatalytic synthesis of coumarin derivativesviaa tandem double bond isomerization/oxidative cyclization of cinnamic acids. Inexpensive and stable xanthone was used as the photocatalyst, and readily available Selectfluor was used as the oxidant. This method tolerates a wide range of functional groups and offers excellent chemical yields in general. Besides, the photocatalytic oxidative cyclization of cinnamic acid esters gives dimerized lignan-type products.
Oxo-Rhenium-Catalyzed Radical Addition of Benzylic Alcohols to Olefins
Bandari, Chandrasekhar,Nicholas, Kenneth M.
, p. 3320 - 3327 (2020/03/23)
Although carbon radicals generated from a variety of alcohol derivatives have proven valuable in coupling and addition reactions, the direct use of alcohols as synthetically useful radical sources is less known. In this report, benzylic alcohols are shown to be effective radical precursors for addition reactions to alkenes when treated with triphenylphosphine or piperidine with the catalyst ReIO2(PPh3)2 (I).
Iron-catalyzed regioselective alkylation of 1,4-quinones and coumarins with functionalized alkyl bromides
Li, Dengke,Shen, Xianfu
supporting information, p. 750 - 754 (2020/02/11)
A simple and efficient Fe-catalyzed regioselective alkylation of 1,4-quinones and coumarins, using functionalized alkyl bromides as alkylating reagents, has been developed. The reaction proceeds under mild conditions with the addition of alkyl bromides to a wide range of 1,4-quinone and coumarin derivatives with a broad substrate scope and wide functional group tolerance to provide the products in good yields. Further application of these strategies could be extended to important biologically active antimalarial lead drugs, such as plasmodione on a gram scale in a single step for medicinal purposes.
Oxidant controlled regioselective mono- and di-functionalization reactions of coumarins
Banerjee, Arghya,Santra, Sourav Kumar,Khatun, Nilufa,Ali, Wajid,Patel, Bhisma K.
, p. 15422 - 15425 (2015/10/20)
C-3 alkylation of coumarins has been accomplished using cycloalkanes or alkylbenzenes in the presence of di-tert-butylperoxide (DTBP) and FeIII catalyst. Under metal free conditions and just by switching the oxidant from DTBP to TBHP, an exclus
Copper-catalyzed regioselective cross-dehydrogenative coupling of coumarins with benzylic Csp3-H bonds
Zhou, Shi-Liu,Guo, Li-Na,Duan, Xin-Hua
supporting information, p. 8094 - 8100 (2015/02/02)
A new copper-catalyzed regioselective cross-dehydrogenative coupling of coumarins with benzylic Csp3-H bonds has been developed. This reaction provides direct access to a wide range of 3-benzylcoumarins in moderate to good yields. The protocol was also extended successfully to other heterocyclic compounds, such as quinolinones.
Catalytic synthesis of coumarins via direct annulations of α,β-unsaturated aldehydes and salicylaldehydes
Gross, Ulrike,Gross, Patrick J.,Shi, Min,Br?se, Stefan
supporting information; experimental part, p. 635 - 638 (2011/04/26)
The first organocatalytic approach towards substituted coumarins is reported. Catalytic amounts of in situ generated N-heterocyclic carbenes (NHC) catalyze a one-pot redox esterification of α,β-unsaturated aldehydes with simultaneous aldol condensation. Georg Thieme Verlag Stuttgart - New York.
Synthesis and pharmacological evaluation of coumarin derivatives as cannabinoid receptor antagonists and inverse agonists
Behrenswerth, Andrea,Volz, Nicole,Toraeng, Jakob,Hinz, Sonja,Braese, Stefan,Mueller, Christa E.
supporting information; experimental part, p. 2842 - 2851 (2009/09/25)
In the present study we synthesized 36 coumarin and 2H-chromene derivatives applying a recently developed umpoled domino reaction using substituted salicylaldehyde and α,β-unsaturated aldehyde derivatives as starting compounds. In radioligand binding stud
Synthesis of 3-alkylcoumarins from salicylaldehydes and α,β-unsaturated aldehydes utilizing nucleophilic carbenes: A new umpoled domino reaction
Toraeng, Jakob,Vanderheiden, Sylvia,Nieger, Martin,Braese, Stefan
, p. 943 - 952 (2008/02/13)
Starting from salicylaldehydes and α,β-unsaturated aldehydes, a new coumarin synthesis in ionic liquids is presented. The key feature is the generation of N-heterocyclic carbenes (NHC) and an Umpolung reaction. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
