52422-07-8Relevant academic research and scientific papers
Sopped-Flow Kinetics of 1-Ethoxy-2,4-dinitronaphthalene with Pyrrolidine and Piperidine in Dimethyl Sulfoxide Solution
Fujinuma, Hajime,Hosokawa, Masaru,Suzuki, Tohru,Sato, Mitsuo,Sekiguchi, Shizen
, p. 1969 - 1975 (1989)
The reaction of 1-ethoxy-2,4-dinitronaphthalene (1) with pyrrolidine or piperidine in dimethyl sulfoxide occured in two stages (Stages I and II).In the stage I, a ?-adduct forms at such a rate as is measured by a stopped-flow technique, and in the stage II it decays at a slower and spectrophotometrically measurable rate.The pyrrolidine system is more reactive than the piperidine system in the stages I and II, with the former reactivity in the stage II being ca. 11000 times higher than the latter.This huge difference was found by NMR evidence to stem from the structure of transition state in the stage II.Further, the activation parameters were determined, which corresponded to such difference in reactivity very well.
Kinetic Studies of the Reactions of Some Phenyl Aryl Sulfides with Aliphatic Amines in Dimethyl Sulfoxide: the Mechanism of Base Catalysis
Chamberlin, Rachel A.,Crampton, Michael R.
, p. 425 - 432 (2007/10/02)
The reaction of n-butylamine, pyrrolidine and piperidine with 4'-R-phenyl 2,4,6-trinitrophenyl sulfides (R = H, Me, Br, NO2), 4a-d, result in the rapid formation of ?-adducts by attack at the unsubstituted 3-position; rate and equilibrium data are reported and substituent effects examined. Attack by amine at the 1-position of of 4a-d, phenyl 2,4-dinitronaphthyl sulfide 9, and phenyl 2,6-dinitro-4-trifluoromethyl sulfide 11, results in displacement of the phenylthio group.The substitutions by butylamine show a first order dependence on the amine concentration indicating that nucleophilic attack is rate determining.However the substitutions by pyrrolidine are subject to general base catalysis and it is argued that here the rate limiting step is deprotonation of the initially formed zwitterionic intermediate.
Aromatic Nucleophilic Substitution Reactions of 1-Dialkylamino-2,4-dinitronaphthalene with Primary or Secondary Amines in Organic Solvents: Facile Amine-Amine Exchange
Sekiguchi, Shizen,Horie, Tohru,Suzuki, Tohru
, p. 698 - 700 (2007/10/02)
The dialkylamino group, (e.g., dimethyl-, diethyl-, and N-n-butyl-N-methylamino, piperidino, and pyrrolidino) of 1-dialkylamino-2,4-dinitronaphthalenes is rapidly replaced by primary amines, particulary in dimethyl sulphoxide; however, substitution does not occur for secondary amines except in the case of pyrrolidine.
Reactions of Secondary amines with Their N-(2,4-Dinitro-1-naphthyl)Derivatives To Form Jackson-Meisenheimer Adducts. Substantial Difference in Reaction Rates between Pyrrolidine and Piperidine
Sekiguchi, Shizen,Bunnett, J. F.
, p. 4871 - 4874 (2007/10/02)
Pyrrolidine, piperidine, and butylmethylamine react with their respective N-(2,4-dinitro-1-naphthyl) derivatives to form ? adducts as through the respective amide ions had attached at the 1 position.These reactions occur in dimethyl sulfoxide solution and proceed to a state of equilibrium.For the pyrrolidine and butylmethylamine reactions, equilibrium constants as well as rate constants both foward and reverse have been measured.Although two amine molecules are required to form the ? adduct, one to supply an amino moiety and the other to receive a proton, the forward reaction is only first order in amine; therefore, amine attack is not base catalyzed.Piperidine reacts so much slower than pyrrolidine, roughly 1/400th as fast, that rate and equilibrium measurements were inconvenient.The low reactivity of the piperidine system is ascribed to stereoelectronic/conformational/steric problems in the piperidino moiety of N-(2,4-dinitro-1-naphthyl)piperidine as it enters the transition state.
Kinetics of Reactions of Cyclic Secondary Amines with 2,4-Dinitro-1-naphthyl Ethyl Ether in Dimethyl Sulfoxide Solution. Spectacular Difference between the Behavior of Pyrrolidine and Piperidine
Bunnett, Joseph F.,Sekiguchi, Shizen,Smith, Lewis A.
, p. 4865 - 4871 (2007/10/02)
The reactions named in the title, which form N-(2,4-dinitro-1-naphthyl) derivatives of these heterocyclic amines, occur in two distinct stages.In stage I, the spectrum of a ?-adduct intermediate develops at a rate which is measurable in a stopped flow apparatus; in stage II, it decays at a slower and easily measurable rate.The kinetics of both stage I and stage II have been studied.Pyrrolidine and piperidine are similar in their stage I behavior, but reactivity in stage II is about 11000 times greater in the pyrrolidine system.This huge difference between systems apparently so similar is judged to arise from steric interactions forced by differences in conformation between the amino moieties in the intermediate ? adducts as they release the nucleofuge.It calls into question the rate-limiting proton transfer interpretation of base catalysis in analogous aminodephenoxylation reactions in protic solvents.
