1737-40-2Relevant academic research and scientific papers
Active esters of N-substituted piperazine acetic acids, including isotopically enriched versions thereof
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Page/Page column 14-15, (2008/06/13)
In some embodiments, this invention pertains to active esters of N-substituted piperazine acetic acid, including isotopically enriched versions thereof. In some embodiments, this invention pertains to methods for the preparation of active esters of N-subs
Isotopically enriched N-substituted piperazines and methods for the preparation thereof
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Page/Page column 14-15, (2008/06/13)
In some embodiments, this invention pertains to isotopically enriched N-substituted piperazines. In some embodiments, this invention pertains to methods for the preparation of isotopically enriched N-substituted piperazines.
Isotopically enriched N-substituted piperazine acetic acids and methods for the preparation thereof
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Page/Page column 14-15, (2008/06/13)
In some embodiments, this invention pertains to isotopically enriched N-substituted piperazine acetic acids. In some embodiments, this invention pertains to methods for the preparation of isotopically enriched N-substituted piperazine acetic acids.
A product analytical study of the thermal and photolytic decomposition of some arenediazonium salts in solution
Canning, Peter S. J.,Maskill, Howard,McCrudden, Katharine,Sexton, Brian
, p. 789 - 800 (2007/10/03)
Products of thermal and photochemical reactions of eleven arenediazonium tetrafluoroborates in various solvents have been analyzed. All compounds in most solvents undergo unimolecular heterolysis to give singlet aryl cations which are captured by solvent. This mechanism is dominant for arenediazonium ions without electron-withdrawing substituents in all solvents, and the only reaction observed in water. Additionally, appreciable yields of fluoroarenes are obtained by fluoride abstraction by the aryl cation from fluorinated solvents and from tetrafluoroborate in fluorinated solvents. Yields from photochemical processes are very similar to those from thermal reactions indicating that the main reactions proceed through common or very similar intermediates. Aryl cations formed from ion-paired diazonium ions may react with the counterion, but fragmentation of dissociated diazonium ions leads only to solvent-derived product. Some arenediazonium ions in some solvents undergo an alternative radical reaction leading principally to hydrodediazoniation. It is proposed that this reaction involves initial rate-limiting electron transfer from ethanol to the arenediazonium ion followed rapidly by homolysis of the resultant aryldiazenyl radical. Within the same solvent cage, the aryl radical then either abstracts an α-hydrogen from the ethanol radical cation generated in the first step to give the reduction product and protonated acetaldehyde, or combines with it at the oxygen to give a protonated aryl ethyl ether.
Fluorodediazoniation in ionic liquid solvents: New life for the Balz-Schiemann reaction
Laali, Kenneth K.,Gettwert, Volker J.
, p. 31 - 34 (2007/10/03)
Drawbacks associated with the classic Balz-Schiemann reaction are eliminated in a series of examples by conducting fluorodediazoniation in ionic liquid solvents, thus opening up a new horizon for a much in demand process.
Neutral Hydrolysis of Substituted Phenyl Trifluoroacetates in Water-Acetonitrile Mixtures with Low Content of Water
Neuvonen, Helmi
, p. 1141 - 1146 (2007/10/02)
The neutral hydrolysis of substituted phenyl trifluoroacetates has been studied in water-acetonitrile mixtures in the region 0.56-3.89M water.The large solvent deuterium isotope effect (kH2O/kD2O) of 2.3 and the thermodynamic activation parameters for the hydrolysis of 4-nitrophenyl and 2,4-dinitrophenyl trifluoroacetates are consistent with a reaction mechanism in which one water molecule acts as a nucleophile and one as a general base.A linear correlation with a slope of 3.4 is found between log kobs and log for the hydrolysis of 4-nitrophenyl trifluoroacetate.This indicates the incorporation of several water molecules in the transition state.The effect of the structure of the leaving group on the rate of the reaction is best explained by a rate-limiting attack on the carbonyl group.
