A NEW REACTION OF OLEFINS, NITRILES, AND HALOGENS¹

Abstract

A new three-component reaction has been discovered for the synthesis of N-(2-chloroalky1)amides. The synthesis involves interaction of chlorine and an olefin in the presence of a nitrile to give an imide chloride that can be hydrolyzed to an N-(2-~hloroalkyl)amide. This interaction of chlorine, an olefin, and a nitrile has been found to be a general reaction applicable to aromatic and aliphatic nitriles and hydrogen cyanide in combination with such olefins as ethylene, cyclohexene, 1-octene, and styrene. In addition, this synthesis can be carried out with bromine to give N-(2-bromoalkyl)amides. The reaction has been shown to proceed in two steps. The first step gives a chloroimide chloride as well as a dichlorohydrocarbon arising from the original olefin, and the second step gives an N-(2-chloroalkyl)amide by hydrolysis of the chloroimide chloride. When hydrogen cyanide is used, the N-(2-chloroalkyl)formamide is very readily hydrolyzed to the corresponding 2-chloroalkylamine, which is isolated as the hydrochloride. Products produced in these various stages have been isolated and identified.The interaction of chlorine and an olefin in the presence of a nitrile is postulated to proceed as follows:I.RCH=CH2 + Cl2 ---+ RCHCHzC1 + C1-

A Comparative Study on the Reactivity of Electrogenerated Bromine with Cyclohexene in Acetonitrile and the Room Temperature Ionic Liquid, 1-Butyl-3-methylimidazolium Bis[(trifluoromethyl)sulfonyl]imide

“…Although a previous report has suggested that DBCH is the product of electrochemical bromination in acetonitrile, 6 two independent studies have shown evidence of solvent incorporation when bromine and cyclohexene are homogeneously mixed in specific molar ratios. 5,11 The NMR evidence of the acetamide product, the absence of a third wave (due to DBCH oxidation) and the catalytic increase seen in the second oxidative wave strongly suggests that DBCH is not produced in this system. We have further supported this proposition by using a computer simulation to model the observed voltammetric response, assuming the reaction mechanism given in Scheme 2, and it is to those simulations which we will next turn our attention.…”

“…The bromination of multiple bonds via electrophillic addition and substitution are well-known reactions and the reactivity of electrogenerated bromine species with a number of organic substrates, including xylene, styrene, phenol, and cyclohexene has been reported in conventional solvents. [5][6][7][8][9][10][11][12][13][14] Herein we report the oxidation of bromide in the roomtemperature ionic liquid, 1-butyl-3-methylimidazolium bis-[(trifluoromethyl)sulfonyl]imide ([C 4 mim][N(Tf) 2 ]) and acetonitrile (MeCN). The subsequent reactivity of the electrogenerated bromine species with cyclohexene is investigated in both solvents and the individual voltammetric responses compared and contrasted.…”

“…The voltammetry of bromide has been investigated in traditional aprotic solvents over the past fifty years. − Most investigations have been performed in acetonitrile, where both the tribromide anion, Br 3 - , and molecular bromine, Br 2 , are reportedly generated upon oxidation. The bromination of multiple bonds via electrophillic addition and substitution are well-known reactions and the reactivity of electrogenerated bromine species with a number of organic substrates, including xylene, styrene, phenol, and cyclohexene has been reported in conventional solvents. − …”

6.07 Ritter-Type Reactions

“…Immediate hydrolysis to the amide was preferable for the alternative case. 103 Higher yields are achieved in the presence of the silver ion (Scheme 30) since the halide ion is removed as the insoluble silver halide, thereby suppressing formation of the vicinal dihalide. 104 Halohydrins also react via the bromonium intermediate in a stereospecific manner.…”

Ritter-Type Reactions of N-Chlorosaccharin: A Method for the Electrophilic Diamination of Alkenes

“…Ring opening of the saccharin ring with potassium ethoxide then gave the chloroamidine ester 5 in 66% overall yield. Formation of 2 is most likely to proceed by ring opening of the initially formed cyclohexene chloronium ion 3 with acetonitrile . The resulting nitrilium ion 4 is then intercepted by the saccharin anion in a classic Ritter-type sequence .…”