3476-67-3Relevant academic research and scientific papers
Diversified facile synthesis of benzimidazoles, quinazolin-4(3H)-ones and 1,4-benzodiazepine-2,5-diones via palladium-catalyzed transfer hydrogenation/condensation cascade of nitro arenes under microwave irradiation
Zhu, Kaicheng,Hao, Jian-Hong,Zhang, Cheng-Pan,Zhang, Jiajun,Feng, Yiqing,Qin, Hua-Li
, p. 11132 - 11135 (2015)
A highly efficient diversified methodology for preparation of benzimidazole, quinazolin-4(3H)-ones and 1,4-benzodiazepine-2,5-diones is established using a palladium-catalyzed transfer hydrogenation (CTH)/condensation cascade of o-nitroaniline and o-nitrobenzamides in a triethylamine-formic acid azeotropic mixture (2:5) under microwave irradiation.
Selective Oxidative Cleavage of 3-Methylindoles with Primary Amines Affording Quinazolinones
He, Junhui,Dong, Jianyu,Su, Lebin,Wu, Shaofeng,Liu, Lixin,Yin, Shuang-Feng,Zhou, Yongbo
supporting information, p. 2522 - 2526 (2020/04/09)
A selective functionalization of C-C-C bonds toward N-C-O bonds is realized by an n-Bu4NI-catalyzed reaction of 3-methylindoles with primary amines using TBHP as the unique oxidant. The systematic process involves oxygenation, nitrogenation, ring-opening, and recyclization, affording a broad range of quinazolinones in good to excellent yields.
N3-Alkylation during formation of quinazolin-4-ones from condensation of anthranilamides and orthoamides
Nathubhai, Amit,Patterson, Richard,Woodman, Timothy J.,Sharp, Harriet E. C.,Chui, Miranda T. Y.,Chung, Hugo H. K.,Lau, Stephanie W. S.,Zheng, Jun,Lloyd, Matthew D.,Thompson, Andrew S.,Threadgill, Michael D.
experimental part, p. 6089 - 6099 (2011/10/08)
Dimethylformamide dimethylacetal (DMFDMA) is widely used as a source of electrophilic one-carbon units at the formate oxidation level; however, electrophilic methylation with this reagent is previously unreported. Reaction of anthranilamide with DMFDMA at 150 °C for short periods gives mainly quinazolin-4-one. However, prolonged reaction with dimethylformamide di(primary-alkyl)acetals leads to subsequent alkylation at N3. 3-Substituted anthranilamides give 8-substituted 3-alkylquinazolin-4-ones. Condensation of anthranilamides with dimethylacetamide dimethylacetal provides 2,3-dimethylquinazolin-4-ones. In these reactions, the source of the N 3-alkyl group is the O-alkyl group of the orthoamides. By contrast, reaction with the more sterically crowded dimethylformamide di(isopropyl)acetal diverts the alkylation to the oxygen, giving 4-isopropoxyquinazolines, along with N3-methylquinazolin-4-ones where the methyl is derived from N-Me of the orthoamides. Reaction of anthranilamide with the highly sterically demanding dimethylformamide di(t-butyl)acetal gives largely quinazolin-4-one, whereas dimethylformamide di(neopentyl)acetal forms a mixture of quinazolin-4-one and N3-methylquinazolin-4-one. The observations are rationalised in terms of formation of intermediate cationic electrophiles (alkoxymethylidene-N,N-dimethylammonium) by thermal elimination of the corresponding alkoxide from the orthoamides. These are the first observations of orthoamides as direct alkylating agents.
