Cycloaddition reactions of heterocyclic azides with 2-cyanoacetamidines as a new route to C , N -diheteroarylcarbamidines

• Published in: Beilstein journal of organic chemistry Vol. 20; no. 1; pp. 17 - 24
• Main Authors: Silaichev, Pavel S, Beryozkina, Tetyana V, Melekhin, Vsevolod V, Filimonov, Valeriy O, Maslivets, Andrey N, Ilkin, Vladimir G, Dehaen, Wim, Bakulev, Vasiliy A
• Format: Journal Article
• Language: English
• Published: Germany Beilstein-Institut 2024
• Subjects: 1,2,3-triazole; 3,3-diaminoacrylonitriles; Chemistry; cornforth rearrangement; cycloaddition reactions; Full Research Paper; heterocyclic azides; heterocyclic azides; Cornforth rearrangement; cycloaddition reactions; 1,2,3-triazole; 3,3-diaminoacrylonitriles
• ISSN: 1860-5397; 1860-5397
• DOI: 10.3762/bjoc.20.3

A novel and efficient base-catalyzed, transition-metal-free method for the synthesis of diheterocyclic compounds connected by an amidine linker, including apart from the common 1,2,3-triazole ring, either an additional pyrimidinedione, 4-nitroimidazole, isoxazole, 1,3,4-triazole, 2-oxochromone or thiazole ring, has been developed. The process was facilitated by a strong base and includes the cycloaddition reaction of 3,3-diaminoacrylonitriles (2-cyanoacetamidines) to heterocyclic azides followed by a Cornforth-type rearrangement to the final products. The reaction is tolerant to various -monosubstituted 3,3-diaminoacrylonitriles and to different heterocyclic azides. The developed method has a broad scope and can be applied to obtain a variety of -heteroaryl-1,2,3-triazole-4-carbimidamides with alkyl, allyl, propargyl, benzyl, cycloalkyl, and indolyl substituents at the position .