A Base Induced Transformation Of A 1,3-Dimethyl-1,3-Di-(1-Adamantyl)Formamidinium Salt Into Beta- Methyl-(1-Adamantyl)Amino Acrylonitriles In Aliphatic Nitriles

A novel 1,3-dimethyl-1,3-di-(1-adamantyl)formamidinium perchlorate has been prepared via the Vilsmeier-Haack reaction of N-methyl-N-(1-adamantyl)formamide and N-methyl-N-(1-adamantyl) amine in a mixture of phosphorus oxychloride and benzene. The new formamidinium salt was found to undergo addition-elimination reactions when treated with sodium hydride in acetonitrile or propionitrile solution, thereby forming the corresponding beta-[methyl(1-adamantyl)amino]acrylonitriles and N-methyl-N-(1-adamantyl) amine. The H-1 and C-13 NMR spectra and the single-crystal X-ray structure of the new formamidinium salt have been determined along with those of the related compound 1,3-di-(1-adamantyl)-1-cyanoamidine and the corresponding beta-(dialkylamino)acrylonitriles.Biochemistr

Tandem Transformations Of 1,2,4-Triazol-5-Ylidenes Into 5-Amidino-1,2,4-Triazoles

The first tandem autotransformations of heteroaromatic carbenes have been found. These reactions involve cleavage of the 1-tert-butyl-3,4-diaryl-1,2,4-triazol-5-ylidenes 1a-d to form benzonitriles and the respective carbodiimides, followed by further reactions of the latter with carbenes 1a-d to afford the 3,4-diaryl-5-(1-tert-butyl-3-arylamidin- 2- yl)-1,2,4- triazoles 5a-d. The X-ray structures of the carbene 1-tert-butyl-3-phenyl-4-n-bromophenyl-1,2,4-triazol-5-ylidene (1a) and the amidinotriazole 3-phenyl-4-p-bromophenyl-5-(1-tert-butyl-3-p-bromophenylamidin-2-yl)- 1,2,4- triazole (5a) were determined. The reactions of 1a with the electrophiles diphenylcarbodiimide, acetonitrile, and diphenyldiazomethane are also described.Biochemistr

Review: Stable Heteroaromatic Carbenes Of The Benzimidazole And 1,2,4-Triazole Series

The review is focused on new data concerning the syntheses and selected properties of stable heteroaromatic monocarbenes of the benzimidazole and 1,2,4-triazole series, biscarbenes, anionocarbenes of the 1,2,4-triazole series, and cryptocarbenes. The syntheses of the precursors to these compounds are also described. Special attention is paid to C-H insertion reactions, X-ray structural data and spectral characteristics of the carbenes and their analogues.Biochemistr