55432-21-8

Upstream product

• 33966-50-6 SEC-BUTYLAMINE 
• 528-29-0 1,2-Dinitrobenzene 

Relevant academic research and scientific papers

Imidazoline derivatives as alpha-1A adrenoceptor ligands

Compound of formula (I) or a pharmaceutically acceptable salt or solvate thereof are disclosed. Such compounds are useful in the treatment of Alpha-1A mediated diseases or conditions such as urinary incontinence.

Kinetics of the Reactions between 1,2-Dinitrobenzene and Aliphatic Primary Amines in Benzene. A Probable Mechanism for the Observed Mild Acceleration

The kinetics of the aromatic nucleophilic substitution (SNAr) between 1,2-dinitrobenzene (1,2-DNB) and n- (BunNH2) and s-butylamine (BusNH2) have been investigated in benzene and hexane-benzene.The second-order rate coefficient for these reactions varies linearly with the amine concentration.However, the ratio of the slope and intercept of the straight lines (k''/k') are in the range for Bunnett's mild acceleration of unclear origin.This is in contrast to the genuine catalysis previously observed for the same reactions in n-hexane.The effect of additives such as pyridine, triethylamine, α-pyridone, and dimethyl sulphoxide was examined.It was found that the catalytic power of the additives qualitatively correlates with Kamlet-Taft's ?* and β parameters rather than with basicity constants of the additives in benzene.On other hand, when the steric requirements for the reactions of BusNH2 are compared with those for BunNH2, for the reaction with 1,2-DNB in benzene it seems that mild acceleration in benzene takes place for the decomposition of the SNAr intermediate.Studies of the reaction of 1,2-DNB with BunNH2 in hexane-benzene give good evidence that benzene forms an electron-donor-acceptor (EDA) complex with 1,2-DNB.It is concluded that, in pure benzene, 1,2-DNB is preferentially solvated by EDA complex formation and consequently the proximity effects either of the nucleophile or any additive will be quite different than in n-hexane.Hence benzene cannot be considered a typical non-polar inert solvent for SNAr reactions.

Aromatic Nucleophilic Substitution Reactions of 1,2-Dinitrobenzene with Aliphatic Primary Amines in n-Hexane; Catalysis by Non-nucleophilic Bases

The kinetics of the reactions of 1,2-dinitrobenzene with n-butyl-, s-butyl-, isobutyl-, n-propyl-, and isopropyl-amine in n-hexane at various temperatures have been investigated.The second-order rate coefficients for these reactions increase linearly with the amine concentrations.The values of the ratio of the rate constant for the catalysed process to the rate constant of the uncatalysed step 3RNH2/k2> are dependent on temperature, so that it is possible to minimize the catalysed or uncatalysed processes simply by temperature variation.Kinetic studies in the presence of non-nucleophilic bases confirmed the proposal that all these reactions are base-catalysed even for the cases where k3RNH2/k2 is less than 50.The role that electron donor-acceptor complex formation between reactants may play in the mechanism of these reactions is discussed.The influence of electronic and steric effects in the amine structure on the catalytic rate constant has been analysed.It has been shown that the catalysed step is disfavoured by electron-donating substituents and that it is inhibited by steric hindrance.The studies with the addition of the bulky bases TEA and TBA confirmed these conclusions.