14491-02-2Relevant articles and documents
Visible-Light Promoted Selective Imination of Unactivated C-H Bonds via Copper-nitrene Intermediates for the Synthesis of 2 H-Azirines
Feng, Liyan,Yang, Chao,Xia, Wujiong
supporting information, p. 8323 - 8327 (2019/10/16)
A novel strategy to trap iminyl radicals with copper ions has been developed at room temperature, the resulted high-valent Cu(III) imine intermediate resets quickly to form nitrene and then to furnish a 2H-azirine. This protocol with dual copper/photoredox catalyst enables the selective imination of unactivated C-H bonds under mild conditions with a broader scope. Moreover, this method also uncovers a novel ring-expansion rearrangement from cyclobutyl oxime derivatives to give the α-acylamino cyclopentanones.
Nitrile imines and nitrile ylides: Rearrangements of benzonitrile N-methylimine and benzonitrile dimethylmethylide to azabutadienes, carbodiimides, and ketenimines. chemical activation in thermolysis of azirenes, tetrazoles, oxazolones, isoxazolones, and oxadiazolones
Begue, Didier,Dargelos, Alain,Berstermann, Hans M.,Netsch, Klaus P.,Bednarek, Pawel,Wentrup, Curt
, p. 1247 - 1253 (2014/03/21)
Flash vacuum thermolysis (FVT) of 1-methyl-5-phenyltetrazole (5b), 2-methyl-5-phenyltetrazole (1b), and 3-methyl-5-phenyl-1,3,4-oxadiazol-2(3H)-one (3b) affords the nitrile imine (2b), which rearranges in part to N-methyl-N′-phenylcarbodiimide (7b). Another part of 2b undergoes a 1,4-H shift to the diazabutadiene (13). 13 undergoes two chemically activated decompositions, to benzonitrile and CH2=NH and to styrene and N 2. FVT of 2,2-dimethyl-4-phenyl-oxazol-5(2H)-one (16) at 400 C yields 3-methyl-1-phenyl-2-azabutadiene (18) in high yield. In contrast, FVT of 3,3-dimethyl-2-phenyl-1-azirene (21) at 600 C or 4,4-dimethyl-3-phenyl- isoxazolone (20) at 600 C affords only a low yield of azabutadiene (18) due to chemically activated decomposition of 18 to styrene and acetonitrile. There are two reaction paths from azirene (21): one (path a) leading to nitrile ylide (17) and the major products styrene and acetonitrile and the other (path b) leading to the vinylnitrene (22) and ketenimine (23). The nitrile ylide PhC -=N+=C(CH3)2 (17) is implicated as the immediate precursor of azabutadiene (18). FVT of either 3-phenylisoxazol- 5(4H)one (25) or 2-phenylazirene (26) at 600 C affords N-phenylketenimine (28). The nitrile ylide PhC-=N+=CH2 (30) is postulated as a reversibly formed intermediate. N-Phenylketenimine (28) undergoes chemically activated free radical rearrangement to benzyl cyanide. The mechanistic interpretations are supported by calculations of the energies of key intermediates and transition states.
Synthesis and Antineoplastic Activity of Bisoxy>methyl>-Substituted 3-Pyrrolines as Prodrugs of Tumor Inhibitory Pyrrole Bis(carbamates)
Anderson, Wayne K.,Milowsky, Arnold S.
, p. 2241 - 2249 (2007/10/02)
A series of bispyrrolines 2-4 were synthesized from either the appropriate α-silylated iminium salt, or an aziridine, or a 2H-azirine in a sequence involving 1,3-dipolar cycloaddition reactions.The antineoplastic activities of the pyrrolines were compared to the corresponding pyrroles.The C-2 gem-dimethyl-substituted pyrroline, 4, which cannot be converted to the pyrrole in vivo, was inactive.The activity of the 2-phenyl-substituted pyrrolines 3 was markedly dependent on the nature of the phenyl substituent, although the correspondingphenylpyrroles all showed comparable activity.The differences in the activities of the pyrrolines 3 may be due to the rate of metabolic conversion of the pyrroline to the pyrrole.Electron-withdrawing substituents on the phenyl ring appear to retard this process.
RADICAL STABILISATION: SYNTHESIS AND DECOMPOSITION OF A β-KETODIAZENE
Zavalsky, Robert C.,Lisiak, Michael,Kovacic, Peter,Luedtke, Al,Timberlake, Jack W.
, p. 425 - 428 (2007/10/02)
The synthesis and decomposition of bis(1,1-dimethyl-2-oxo-2-phenylethyl)diazene (7e) is described.The presence of a carbonyl group adjacent to a radical center greatly enhances the radical stability.