A solid hydrazine was isolated as a crystalline powder by reacting aqueous hydrazine with supercritical CO(2). Its structure determined by single crystal X-ray diffraction shows a zwitterionic form of NH(3)(+)NHCO(2)(-). The solid hydrazine is remarkably stable but is as reactive as liquid hydrazine even in the absence of solvents.
Ionic hydrogenation of azines: An efficient synthesis of 1,2-dialkylhydrazines
作者:Dario Perdicchia
DOI:10.1016/j.tet.2023.133432
日期:2023.6
An efficient synthetic method of ionic hydrogenation of azine to the corresponding 1,2-dialkylhydrazines was accomplished. Reaction time was fast and isolation and purification of the 1,2-dialkylhydrazines were operationally simple. Yields were almost quantitative for most of the products with good functional group tolerance. Moreover, the byproduct of reduction gave the opportunity for the selective
Elguero,J. et al., Bulletin de la Societe Chimique de France, 1967, p. 3005 - 3019
作者:Elguero,J. et al.
DOI:——
日期:——
2,3-Diaza-1,3-dienes (Azines) as Substrates for the Staudinger Reaction. Synthesis and Reactivity of N-Imino-.beta.-lactams
作者:Benito Alcaide、Miguel Miranda、Javier Perez-Castells、Concepcion Polanco、Miguel A. Sierra
DOI:10.1021/jo00105a014
日期:1994.12
The reaction of aromatic and aliphatic azines with different ketene precursors, such as the acid chloride/Et(3)N system, alkoxychromium(0) carbenes, and free diphenyl ketene, gives N-imino-beta-lactams in good to excellent yields, with good levels of cis,trans-selectivity. A wide variety of symmetrically-substituted azines derived from aldehydes and ketones are compatible with the Staudinger reaction. Chiral N-imino-beta-lactams derived from symmetrically or unsymmetrically (mixed) chiral azines are also obtained in good yields as essentially single enantiomers (de > 95%). Different reaction intermediates, including hemiaminals, oxadiazols, and hydrazides have been isolated. Free diphenyl ketene forms Diels-Alder adducts and N-acylazadienes in addition to the previously reported N-imino-beta-lactams, The usual reactivity of the beta-lactam ring is modified in N-imino-beta-lactams by the presence of the imino group. Thus, beta-hydrazonoesters, N-alkylamino-beta-lactams, and NH-beta-lactams can be efficiently obtained by base-catalyzed 2-azetidinone ring opening, catalytic hydrogenation, and ozonolysis, respectively.
BAGROV, F. V., ZH. OBSHCH. XIMII, 59,(1989) N, S. 1320-1325