Amidinium acetates

Alkyl A-2-selenazolines, preparation. 259 Amidinium ion, ionic system of, 68 2-Amino-4-aryl-5-acetic acid selenazoles. 

Enediamines 35,103 and 104, derived from piperidine, react readily with acids to form the amidinium salts 105-107. The perchlorate salts are particularly easy to prepare since they crystallize in analytically pure form on titration of the parent compound with 0.1 N perchloric acid in acetic acid (equation 36)84. Secondary 1,1-enediamines 8 and 53 give amidinium salts almost quantitatively on treatment with hydrochloric acid in methanol29,85. The evidence for formation of amidinium salts has been provided by the... 

Diethylamine acetate Pyridiniiim salt T etramethylammonium acetate, Tetraethyl-ammonium-Piperidinium acetate Isoxazolium salts Trialky loxonium salt Amidinium salts Ketenimines Diazo compounds Diazomethane, Phenyl-diazomethane K-methy Idiazotate Hexamethylenetetramine Azo compounds Azodicarboxamide ROOC-N N-COOR A zodiisobuty ronitrile T riazenes Azidinium salts p-Nitrobenzene-diazonium sulfate Sulfanilic acid, diazotized... 

Acetates of organic bases Diethylamine acetate Pyridinium salt Tetramethylammonium acetate, Tetraethyl-ammonium-Piperidinium acetate Isoxazolium salts Trialkyloxonium salt Amidinium salts Ketenimines Diazomethane K-methyldiazotate... 

Pyrrolidinium acetate Piperidinium -Isoxazolium salts Trialky loxonium salt Amidinium salts Ketenimines Benzaldoxime Hy dr azobenzene Diazo compounds Diazomethane, Phenyl-diazomethane Ethyl diazoacetate K-methyldiazotate Hexamethylenetetramine Azo compds., Azobenzene Acylazo compds. Azodicarboxamide ROOC-N N-COOK Azodiisobutyronitrile Triazenes Diazonium fluoro-borates... 

Hruby and co-workers utilized the Ca-symmetric pyrrolidine derivative as an auxiliary for asymmetric induction in studies of the Meerwein-Claisen rearrangement to yield tram )6-alkyl y, -unsaturated amino acids (334). Treatment of amide 330 wiA a reaetive alkylating agent yielded the amidinium ion 331 which was trapped with alkoxide 332. Upon warming to the ambient temperature, the ketene iV.O-acetal underwent diastereoselective Meerwein-Claisen rearrangement to 334 in excellent yield with high stereocontrol. 

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