Sulfate Radical Anion (SO4•–) Mediated C(sp3)–H Nitrogenation/Oxygenation in N-Aryl Benzylic Amines Expanded the Scope for the Synthesis of Benzamidine/Oxazine Heterocycles
摘要:
A transition-metal-free, K2S2O8-mediated intra-molecular, oxidative nitrogenation/oxygenation of C(sp(3))-H in N-aryl benzylic amines followed by oxidation at the benzylic center has been developed for the synthesis of benzamidine/benzoxazine heterocycles, providing an expedient access to quinazolin-4(3H)-ones, N-aryl-2-arylbenzimidazoles, and 4H-3,1-benzoxazin-4-ones. A considerable amount of work dealing with the mechanistic study to understand the crucial intramolecular cyclization step largely favors an iminium ion as the key intermediate.
DMAP-Catalyzed Domino Reactions of α-Chloroaldoxime O-Methanesulfonates and 2-Aminobenzoic Acids for the Synthesis of Quinazolinediones
作者:Juthanat Kaeobamrung、Watcharadet Kaewman
DOI:10.1055/a-2107-5653
日期:2023.10
α-chloroaldoxime O-methanesulfonates via DMAP-catalyzed domino reactions under mild reaction conditions in one-pot fashion. Chemical transformations involved nucleophilic substitution, Tiemann rearrangement, and cyclic urea formation. The strength of nitrogennucleophile of 2-aminobenzoic acids and the high level of carbon electrophile of α-chloroaldoxime O-methanesulfonates were crucial for the reaction
Dilactams. Synthesis of nonsymmetrical dibenzodiazocinediones 1
作者:Alfred Hassner、Bin Sun、Gary Gellermann、Simcha Meir
DOI:10.1016/j.tetlet.2003.12.079
日期:2004.2
We report the first examples of nonsymmetrical dibenzodiazoeinediones, mono-, di-, tri- and tetra-substituted in the aromatic rings including a benzo pyridino diazocine, by a new short method without the requirement of protection. The procedure involves conversion of an anthranilic acid to its sulfinamide lactone followed by direct heating with a different N-alkylanthranilic acid. (C) 2003 Elsevier Ltd. All rights reserved.