65050-85-3Relevant academic research and scientific papers
Asymmetric synthesis of tetrahydropyran[3,2-c]quinolinones via an organocatalyzed formal [3 + 3] annulation of quinolinones and MBH 2-naphthoates of nitroolefin
Li, Jian,Hu, Qi-Long,Chen, Xue-Ping,Hou, Ke-Qiang,Chan, Albert S.C.,Xiong, Xiao-Feng
supporting information, p. 697 - 700 (2019/09/30)
An efficient asymmetric and enantio-swithchable organocatalytic [3 + 3] annulation reaction using MBH-2-naphthoates of nitroalkenes and 4-hydroxyquinolin-2(1H)-ones has been developed. Densely substituted tetrahydropyrano[3,2-c]quinolinones scaffolds with two adjacent stereogenic centers are obtained with high yield (up to 95% yield) and good stereoselectivities (up to >20:1 dr and 96% ee) in an enantio-switchable manner. Furthermore, gram scale synthesis was achieved and the nitro group could easily transform into an amino group without any appreciable loss in the diastereo- and enantioselectivity.
Tert-Butyl Hydroperoxide and Tetrabutylammonium Iodide-Promoted Free Radical Cyclization of α-Imino-N-arylamides and α-Azido-N-arylamides
Li, Dianjun,Yang, Tonghao,Su, Hailin,Yu, Wei
supporting information, p. 2529 - 2539 (2015/08/18)
The oxidizing system of tert-butyl hydroperoxide (TBHP) and tetrabutylammonium iodide (TBAI) is capable of generating α-(arylaminocarbonyl)iminyl radicals from ethyl 2-(N-arylcarbamoyl)-2-iminoacetates. These iminyl radicals preferably undergo intramolecular ipso attack on the benzene ring to give azaspirocyclohexadienyl radicals, which are readily captured by molecular oxygen under an oxygen atmosphere to yield azaspirocyclohexadienones. In the absence of oxygen, the reaction affords quinoxalin-2-one products. This oxidizing system is also effective to convert α-aryl-α-azido-N-arylamides to the corresponding iminyl radicals under basic conditions (sodium tert-butoxide, t-BuONa), and the subsequent cyclization of these iminyl radicals results in the formation of azaspirocyclohexadienone products in high yields under an oxygen atmosphere. Plausible mechanisms are proposed to rationalize the experimental results, and factors influencing the reactions are discussed.
Malonic ester amide synthesis: An efficient methodology for synthesis of amides
Mahajan, Pankaj S.,Mahajan, Jyoti P.,Mhaske, Santosh B.
, p. 2508 - 2516 (2013/07/25)
A general methodology malonic ester amide synthesis has been demonstrated, which uses α-substituted/unsubstituted diethyl malonates for the decarboxylative acylation of various aromatic/heteroaromatic primary/secondary amines to form one-carbon homologated amides, thus providing easy access to amides with odd/even chain lengths and an array of substituents on the alkyl/aryl part while avoiding use of acyl chlorides or peptide coupling reagents. Copyright
Carbene radicals in cobalt(II)-porphyrin-catalysed carbene carbonylation reactions; A catalytic approach to ketenes
Paul, Nanda D.,Chirila, Andrei,Lu, Hongjian,Zhang, X. Peter,Debruin, Bas
supporting information, p. 12953 - 12958 (2013/10/01)
One-pot radicals: Cobalt(III)-carbene radicals, generated by metallo-radical activation of diazo compounds and N-tosylhydrazone sodium salts with cobalt(II) complexes of porphyrins, readily undergo radical addition to carbon monoxide, allowing the catalytic production of ketenes. These ketenes subsequently react with various amines, alcohols and imines in one-pot tandem transformations to produce differently substituted amides, esters and β-lactams in good isolated yields. Copyright
Phenyliodine bis(trifluoroacetate)-mediated oxidative C-C bond formation: Synthesis of 3-hydroxy-2-oxindoles and spirooxindoles from anilides
Wang, Junwei,Yuan, Yucheng,Xiong, Rui,Zhang-Negrerie, Daisy,Du, Yunfei,Zhao, Kang
supporting information; experimental part, p. 2210 - 2213 (2012/06/18)
The reaction of phenyliodine bis(trifluoroacetate) (PIFA) with a series of anilides 1 (E = CO2Et) in CF3CH2OH was found to give 3-hydroxy-2-oxindole derivatives 2, while that with various anilides 1′ (E = CON(R4
Pd-catalyzed carbonylation of diazo compounds at atmospheric pressure: A catalytic approach to ketenes
Zhang, Zhenhua,Liu, Yiyang,Ling, Lin,Li, Yuxue,Dong, Yian,Gong, Mingxing,Zhao, Xiaokun,Zhang, Yan,Wang, Jianbo
supporting information; experimental part, p. 4330 - 4341 (2011/06/21)
The carbonylation of carbenes through catalytic cycles is highly desirable due to the importance of ketene-mediated reactions in organic synthesis. In this investigation, a highly efficient and mild catalytic approach toward ketene intermediates has been developed based on Pd-catalyzed carbonylation of diazo compounds with CO. When α-diazocarbonyl compounds or N-tosylhydrazone salts are heated in the presence of a palladium catalyst under atmospheric pressure of CO, ketene intermediates are formed in situ, where they undergo further reactions with various nucleophiles such as alcohols, amines, or imines. The Pd-catalyzed tandem carbonylation-Staudinger cycloaddition gives β-lactam derivatives in good yields with excellent trans diastereoselectivity. The results from DFT calculation on the reaction mechanism suggest that Pd is involved in the [2 + 2] cycloaddition process and affects the diastereoselectivity of the β-lactam products by assisting isomerization of the addition intermediate. On the other hand, the acylketenes generated from the Pd-catalyzed carbonylation of α-diazoketones react with imines in a formal [4 + 2] cycloaddition manner to afford 1,3-dioxin-4-one derivatives. This straightforward carbonylation provides a new approach toward highly efficient catalytic generation of ketene species under mild conditions.
Acetohydroxamic acids
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, (2008/06/13)
The invention provides new acetohydroxamic acid derivatives, having interesting properties on the central nervous system, of the formula: R1 R2 R3 C-CO-NHOH, in which R2 and R3 are each hydrogen or C1-6 alkyl, and R1 is C1-6 alkyl Z1 Z2 N (where Z1 and Z2 are each phenyl, substituted phenyl, or cycloalkyl), substituted hydantoinyl, benzhydroxylcarboxamido, Z3 CH2 -- (where Z3 = optionally substituted aryl), Z4 -A- (where Z4 is optionally substituted phenyl or naphthyl, and A is --NH--, --N(C1-4 alkyl)--, --N(C5-6 cycloalkyl)--, --NHCO--, --N(C1-4 alkyl)CO--, --N(C5-6 cycloalkyl)CO--, --CONH--, --CON(C1-4 alkyl)--, --CON(C5-6 cycloalkyl)--, --NHCONH--, --N(C5 H6)CONH--, or --N(substituted phenyl)CONH--, optionally substituted benzimidazolyl, or an optionally substituted tricyclic radical, and their metal and acid addition salts.
