36567-89-2Relevant academic research and scientific papers
α-Keto Acids as Triggers and Partners for the Synthesis of Quinazolinones, Quinoxalinones, Benzooxazinones, and Benzothiazoles in Water
Huang, Jian,Chen, Wei,Liang, Jiazhi,Yang, Qin,Fan, Yan,Chen, Mu-Wang,Peng, Yiyuan
, p. 14866 - 14882 (2021/10/25)
A general and efficient method for the synthesis of quinazolinones, quinoxalinones, benzooxazinones, and benzothiazoles from the reactions of α-keto acids with 2-aminobenzamides, benzene-1,2-diamines, 2-aminophenols, and 2-aminobenzenethiols, respectively, is described. The reactions were conducted under catalyst-free conditions, using water as the sole solvent with no additive required, and successfully applied to the synthesis of sildenafil. More importantly, these reactions can be conducted on a mass scale, and the products can be easily purified through filtration and washing with ethanol (or crystallized).
An efficient transition-metal-free route to quinazolin-4(3H)-onesvia2-aminobenzamides and thiols
Dong, Yibo,Wu, Yangjie,Yan, Congcong,Yang, Jinchen,Zhang, Jinli
supporting information, p. 15344 - 15349 (2021/09/07)
An efficient approach to quinazolin-4(3H)-ones was developed by a one-pot intermolecular annulation reaction ofo-amino benzamides and thiols. This method has the features of good functional group tolerance, being transition metal and external oxidant free, and easy operation. Varieties of 2-aryl (heteroaryl) quinazolin-4(3H)-one, 2-phenyl-pyrido[2,3-d]pyrimidin-4(3H)-one and 3-phenyl-2H-1,2,4-benzo thiadiazine-1,1-dioxide derivatives were obtained with a yield of up to 98%. The control experiment revealed that the thiol substrate could promote the dehydroaromatization step.
Direct Use of Benzylic Alcohols for Multicomponent Synthesis of 2-Aryl Quinazolinones Utilizing the π-Benzylpalladium(II) System in Water
Hikawa, Hidemasa,Nakayama, Taku,Takahashi, Makiko,Kikkawa, Shoko,Azumaya, Isao
supporting information, p. 4075 - 4084 (2021/07/26)
We demonstrate the direct use of benzylic alcohols for a multicomponent reaction of readily available isatoic anhydrides with amines in water, which is a synthetic route for the direct construction of a series of 2-aryl quinazolinones. This one-pot synthetic method involves the dehydrative N-benzylation of in situ generated anthranilamides followed by an amide-directed benzylic C?H amination process utilizing the π-benzylPd(II) system. Comparison of independent rate measurements using benzyl alcohol and its deuterated form gave a kinetic isotope effect of 3.5. Therefore, the benzylic C?H bond is cleaved in the rate-determining step. We successfully carried out a gram-scale reaction in 85% yield with simplified product isolation. (Figure presented.).
Direct synthesis of quinazolinones via the carbon-supported acid-catalyzed cascade reaction of isatoic anhydrides with amides and aldehydes
Zhang, Xiangyu,Luo, Chujun,Chen, Xiaoyong,Ma, Weilin,Li, Bin,Lin, Zirui,Chen, Xiuwen,Li, Yibiao,Xie, Feng
supporting information, (2021/02/20)
A novel catalytic system is reported for the construction of quinazolinones via the carbon-supported acid-catalyzed cascade coupling of isatoic anhydrides with amides and aldehydes. Subsequent selective hydrosilylation of the quinazolinones using a hydrogen-transfer strategy was also explored to provide dihydroquinazolines with structural diversity. The developed methodology proceeds with a broad substrate scope, excellent functional group tolerance, and utilizes a reusable catalyst and air as a green oxidant.
KOtBu-BF3.OEt2 mediated synthesis of quinazolin-4(3H)-ones from 2-substituted amides with nitriles and aldehydes
Nomula, Vishnuvardhan,Rao, Sadu Nageswara
, p. 2602 - 2612 (2021/08/03)
KOtBu-BF3.OEt2 mediated synthesis of quinazolin-4(3H)-ones from 2-substituted amides with nitriles and aldehydes have been developed. In this protocol, a variety of nitriles as well as aldehydes react with 2-substituted benzamides to corresponding quinazolin-4(3H)-ones products in good to moderate yields, via the cleavage of C-X and C-N bonds and the formation of double C-N bonds simultaneously, in presence of potassium tert-butoxide.
Synthesis of 2-aryl quinazolinones: Via iron-catalyzed cross-dehydrogenative coupling (CDC) between N-H and C-H bonds
Jang, Yoonkyung,Lee, Seok Beom,Hong, Junhwa,Chun, Simin,Lee, Jeeyeon,Hong, Suckchang
supporting information, p. 5435 - 5441 (2020/08/03)
Herein, we describe the direct synthesis of quinazolinones via cross-dehydrogenative coupling between methyl arenes and anthranilamides. The C-H functionalization of the benzylic sp3 carbon is achieved by di-t-butyl peroxide under air, and the subsequent amination-aerobic oxidation process completes the annulation process. Iron catalyzed the whole reaction process and various kinds of functional groups were tolerated under the reaction conditions, providing 31 examples of 2-aryl quinazolinones using methyl arene derivatives in yields of 57-95percent. The synthetic potential has been demonstrated by the additional synthesis of aryl-containing heterocycles. This journal is
Synthesis of Quinazoline and Quinazolinone Derivatives via Ligand-Promoted Ruthenium-Catalyzed Dehydrogenative and Deaminative Coupling Reaction of 2-Aminophenyl Ketones and 2-Aminobenzamides with Amines
Kirinde Arachchige, Pandula T.,Yi, Chae S.
supporting information, (2019/05/08)
The in situ formed ruthenium catalytic system ([Ru]/L) was found to be highly selective for the dehydrogenative coupling reaction of 2-aminophenyl ketones with amines to form quinazoline products. The deaminative coupling reaction of 2-aminobenzamides with amines led to the efficient formation of quinazolinone products. The catalytic coupling method provides an efficient synthesis of quinazoline and quinazolinone derivatives without using any reactive reagents or forming any toxic byproducts.
Pd-Catalyzed Regioselective Mono-Arylation: Quinazolinone as the Inherent Directing Group for C(sp2)-H Activation
Garad, Dnyaneshwar N.,Viveki, Amol B.,Mhaske, Santosh B.
, p. 6366 - 6372 (2017/06/23)
The Pd-catalyzed quinazolinone-directed regioselective monoarylation of aromatic rings by C-H bond activation is developed. A broad substrate scope is demonstrated for both quinazolinone as well as diaryliodonium triflates. The use of a base was found to be crucial for this transformation, unlike for the known nitrogen-directed arylations. All of the novel quinazolinones of biological interest were synthesized by using the operationally simple Pd(II)-catalyzed arylation reaction.
I2-Catalyzed cross dehydrogenative coupling: Rapid access to benzoxazinones and quinazolinones
Chen, Kaili,Gao, Biao,Shang, Yanguo,Du, Jianyao,Gu, Qinlan,Wang, Jinxin
, p. 8770 - 8779 (2017/11/03)
An efficient and applicable I2-catalyzed intramolecular dehydrogenative C-O/C-N coupling reaction via activating the C-H bond adjacent to the N atom has been developed to provide dozens of substituted benzoxazinones (31 examples) and quinazolinones (5 examples) in good to excellent yields (up to 98%). This one-pot methodology has significant advantages, including a metal-free process, broad substrate scope, high atom economy, and simple operation. This strategy goes through an iminium intermediate followed by nucleophilic attack to provide the desired products.
Synthesis of Cu-catalysed quinazolinones using a Csp3-H functionalisation/cyclisation strategy
Gholap, Aniket V. A.,Maity, Soham,Schulzke, Carola,Maiti, Debabrata,Kapdi, Anant R.
, p. 7140 - 7146 (2017/09/07)
A series of 2,3-disubstituted-4(3H)-quinazolinones were synthesised via a copper-catalysed Csp3-H functionalisation/cyclisation of 2-amino-N,N-dialkylbenzamides. In comparison to the reported methods this strategy allows an easy access to diversely substituted quinazolinones under mild conditions in air. The reaction also exhibits good functional group tolerance and would be of value to heterocyclic researchers as well as pharmaceutical process chemists. The reaction is proposed to proceed through a double SET type radical mechanism.
