125847-92-9Relevant academic research and scientific papers
Mizoroki-Heck Reaction of Unstrained Aryl Ketones via Ligand-Promoted C-C Bond Olefination
Wang, Mei-Ling,Xu, Hui,Li, Han-Yuan,Ma, Biao,Wang, Zhen-Yu,Wang, Xing,Dai, Hui-Xiong
, p. 2147 - 2152 (2021/04/05)
Mizoroki-Heck reaction of unstrained aryl ketone with acrylate/styrene is accomplished via palladium-catalyzed ligand-promoted C-C bond cleavage. Various (hetero)aryl ketones are compatible in the reaction, affording the alkene product in good to excellent yields. Further applications in the late-stage olefination of some drugs, natural products, and fragrance-derived aryl ketones demonstrate the synthetic utility of this protocol. By employing ketone as both the directing group and the leaving group, 1,2-bifunctionalization is achieved via sequential ortho-C-H alkylation/ipso-Heck olefination.
Ligand-Promoted Alkynylation of Aryl Ketones: A Practical Tool for Structural Diversity in Drugs and Natural Products
Xu, Hui,Ma, Biao,Fu, Zunyun,Li, Han-Yuan,Wang, Xing,Wang, Zhen-Yu,Li, Ling-Jun,Cheng, Tai-Jin,Zheng, Mingyue,Dai, Hui-Xiong
, p. 1758 - 1764 (2021/02/09)
Conversion of the numerous aryl ketones into aryl electrophiles via Ar-C(O) cleavage remains a challenging yet highly desirable transformation in Sonogashira-type coupling. Herein, we report a palladium-catalyzed ligand-promoted alkynylation of unstrained aryl ketones. The protocol allows the alkynylation to be carried out in a one-pot procedure with broad functional-group tolerance and substrate scope. The potential applications of this protocol in drug discovery and chemical biology are further demonstrated by late-stage diversification of a number of pharmaceuticals and natural products. More importantly, two different biologically important fragments derived from a pharmaceutical and natural product could be connected by the consecutive alkynylation of ketones. Distinct from aryl halides in conventional Sonogashira reactions, the protocol provides a practical tool for the 1,2-bifunctionalization of aryl ketone by merging ketone-directed ortho-C-H activation with ligand-promoted ipso-Ar-C(O) alkynylation.
Radical cyanomethylation via vinyl azide cascade-fragmentation
Donald, James R.,Berrell, Sophie L.
, p. 5832 - 5836 (2019/06/17)
Herein, a novel methodology for radical cyanomethylation is described. The process is initiated by radical addition to the vinyl azide reagent 3-azido-2-methylbut-3-en-2-ol which triggers a cascade-fragmentation mechanism driven by the loss of dinitrogen and the stabilised 2-hydroxypropyl radical, ultimately effecting cyanomethylation. Cyanomethyl groups can be efficiently introduced into a range of substrates via trapping of α-carbonyl, heterobenzylic, alkyl, sulfonyl and aryl radicals, generated from a variety of functional groups under both photoredox catalysis and non-catalytic conditions. The value of this approach is exemplified by the late-stage cyanomethylation of pharmaceuticals.
An improved synthesis of β-cyano- l -alanine esters and amides
Wang, Guoxin,Chen, Longjian,Cai, Xiaodan,Li, Zigang,Luo, Ming
, p. 309 - 312 (2016/01/20)
We have developed a novel, mild, efficient, and scalable protocol for the synthesis of N-protected β-cyano-l-alanine esters or -amides from N-protected l-asparagin. This protocol avoided the use of toxic or unpleasant reagents and was easy to operate in laboratory.
Cobalt Carbonyl Mediated Michael Addition: Direct Synthesis of Esters Containing Other Functional Groups from Activated Olefins
Sisak, Attila,Ungvary, Ferenc,Marko, Laszlo
, p. 2508 - 2513 (2007/10/02)
Hydrocarbalkoxylation of acrylonitrile with stoichiometric amounts of alcohols in the presence of catalytic amounts of Co2(CO)8 and pyridine bases leads to 2,4-dicyano-2-methylbutanoic acid esters.The yield of these Michael adducts shows a maximum as a function of the pyridine/cobalt ratio.Analogues reactions using equimolar amounts of alcohol, acrylonitrile, and an other activated olefin result in products with at least three different functional groups.Acrylonitrile with pyH gives (1-cyanoethyl)cobalt tetracarbonyl, which is proposed to be the key intermediate of the hydrocarbalkoxylation.This complex may be deprotonated to a "Michael donor" anion, i.e. the Michael adducts are most probably formed in a cobalt-mediated way.The above catalytic system promoted also the Michael addition of some C-H acids to activated olefins under atmospheric conditions.
