Ketones, aziridinyl synthesis

Synthesis of Aziridinyl Ketones and Their Chemical Properties... 

For synthesis of N-substituted aziridinyl ketones, primary amines such as methylamine [11, 12, 13], cyclohexylamine [8, 11, 14, 15, 16, 17] and benzyla-mines [17, 18, 19, 20] are introduced in the reaction instead of ammonia. These reactions can be carried out in different solvents, such as alcohols, benzene, toluene, dimethylformamide, etc. On the basis of this chemistry, aziridinyl ketones containing either one or more three-membered cycles can be synthesized (e.g., compounds 7 and 10 Scheme 1.3). 

It is known that the first stage of the reaction of a,/ -dibromoketones with amines is their dehydrobromination leading to ce-bromo derivatives [9, 21]. o-Bromochalcones are mentioned in the literature and also can be used for the synthesis of aziridinyl ketones [8,11, 22, 23, 24, 25]. For example, Khomutov et al. [25] carried out the synthesis of the dodecafluoro derivative 13 by the interaction of the corresponding a-bromoketone 11 with hexylamine 12 (Scheme 1.4). 

One-pot synthesis of aziridinyl ketones including the initial dipolar addition of azides to the ethylene bond with subsequent elimination of the nitrogen by photolysis is also possible [55, 56]. For example, in the case of azidocarboxylic acid ethyl ester 35,2-oxo-7-azabicyclo[4.1.0]heptane-7-carboxylic acid ethyl ester 37 was synthesized via the formation of the cycloadduct 36 [55] (Scheme 1.10). 

The processes involving the aziridine cycle are very diverse. For instance, reactions of alkylation by alkyl halogenides [63], bromoacetic acid derivatives [29, 30] and acetoxypropene [64], are known. The use of arylboronic acids for synthesis of TV-alkyl derivatives, e.g., compound 45, is described in [63] (Scheme 1.13). The one-step reaction at room temperature of aziridinyl ketones 46 with chloroacetamides 47 and sulfur in the presence of Et3N yields mono-thio-oxamidines 48 [65]. 

An example of azaheterocycle synthesis based upon aziridinyl ketones is also a reductive cyclization of l-cyclohexyl-2-benzoyl-3-(2-nitrophenyl)aziridine 68 into quinoline 69 [14] (Scheme 1.18). 

Pashkevich and Khomutov [111] reported the synthesis of aziridines containing polyfluoroalkyl substituents on the aziridine cycle. In the case where RF is CF3, the only reaction product is bis(aziridinyl ketone) 103 (Scheme 1.28). The results also provide information about the reaction mechanism. As well as in [107], it is assumed that the reaction proceeds via the formation of a-bromo-ketones and /5-aminoketones 101 and 102 where the next step is the intramolecular bromine substitution and heterocyclization into quinoxaline 104. But in the case where RF is CF3, the formation of the aziridine cycle is followed by the interaction of the second amino group of the diamine with another molecule of the intermediate 102, leading to compound 103. 

The first chapter is devoted to the formation and subsequent modification of three-membered heterocycles—aziridines. Synthesis and properties of aziridinyl ketones, bi- and tricyclic aziridine derivatives, cycloaddition and photochemical reactions are described. The second chapter deals with... 

Professor Stanislaw Lesniak was born in 1952 in Gorlice (Poland). He obtained his M.Sc. degree in chemistry from the University of Lodz (Poland) in 1976, studying the reactivity of aziridines. He received his Ph.D. in chemistry from the same university in 1983 for study of stereoselective reduction of aziridinyl ketones. He presented his habilitation thesis at the University of Lodz in 1996. Professor Lesniak lectured at the University of Lodz from 1977 and six months at the University Claude-Bernard Lyon 1 in 1987/1988. He was a research fellow in the Department of Chemistry at the University Claude-Bernard Lyon 1 in a group of Prof. Andre Laurent in 1984-85, 1987-1988, and 1991-92. At the same university, he was employed as a CNRS research worker in 2001-02 in the group of Prof. P. Goekjian. The focus of his studies has been synthesis and reactivity of small molecules, radical reactions, and reactions under flash vacuum thermolysis conditions. 

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