Kinetics nucleophilic aliphatic

Kinetics of the transformations of the N-F class of fluorinating agents in water, acetonitrile, alcohols, and aqueous solutions of alkali metal hydroxides have been studied.159 Other kinetic studies include die reactions of triphenylphosphine with 3-methoxy- or 3-acctoxy-4,4,5,5-tetrasubstitutcd-1,2-dioxolanes,160 the reactions of 2-amino-5-chlorobenzophenone witii HC1 in MeOH-H20 (die aspect of nucleophilic aliphatic substitution lies in certain products arising from attack of AH2 on CH3OH there are six products in all, and rate constants are evaluated for die formation of each of them),161 and the hydrolysis of derivatives of diazidophenyhnethane.162... 

Just because this reaction is simiiar to the previous nucleophilic aliphatic substitution, one should not jump to the conclusion that the rate law and kinetics wilt be similar. The rate Uzw is determined from experimental obsen/atiam It relates the rate of reaction at a particular point to the species concentrations at that same point. In this case if one consults an organic chemistry text, one will find that the rate law is... 

The field of chemistry that deals with rates of reaction, and in particular with dependence of rates on concentration, is called kinetics. Let us see what kinetics can tell us about nucleophilic aliphatic substitution. 

As is the case with nucleophilic aliphatic substitution, nucleophilic aromatic substitution (SNAr) can occur by processes that exhibit either first- or second-order kinetics. In contrast to the aliphatic reactions, however, the first-and second-order aromatic reactions are quite different in character. 

Mechanism and structure, in organic electrochemistry, 12, 1 Mechanism of the dissociative reduction of C—X and X—X bonds pCl/40, S), kinetics and, 36, 85 Mechanisms for nucleophilic aliphatic substimtion at glycosides,... 

The following studies, some involving kinetics, are also of interest for nucleophilic aliphatic substitution. 

Most of the kinetic measures of solvent effects have been developed for the study of nucleophilic substitution (Sn) at saturated carbon, solvolytic reactions in particular. It may, therefore, be helpful to give a brief review of aliphatic nucleophilic substitution. Two mechanistic routes have been clearly identified. One of these is shown by... 

Aromatic nitrations, 17 160-161 by-products of, 17 161 kinetics of, 17 162 Aromatic nitriles, 17 243 Aromatic nucleophilic displacement, polyimide synthesis via, 20 273 Aromatic phosphines, 19 60, 62 Aromatic poly(monosulfide ketone)s, 23 709 Aromatic poly(monosulfide)s, 23 706 Aromatic polyamide copolymers, laboratory synthesis of, 19 720 Aromatic polyamide fibers, 24 614 Aromatic polyamides, 10 210-212 19 713-738. See also Aliphatic polyamides (PA)... 

Other terms that he invented include the system of classification for mechanisms of aromatic and aliphatic substitution and elimination reactions, designated SN1, SN2, El, and E2. "S" and "E" refer to substitution and elimination, respectively, "N" to nucleophilic, and "1" and "2" to "molecularity," or the number of molecules involved in a reaction step (not kinetic order, having to do with the equation for reaction rate and the concentration of reactants). Ingold first introduced some of these ideas in 1928 in a... 

Dimer presence in apolar solvents is indicated as being responsible for some particular kinetic features when protic amines are nucleophilic reagents87,88. Aliphatic amines are slightly more associated than aromatic amines89-91. 

The kinetics of the reactions of 1-halo-2,4-dinitrobenzenes with aliphatic amines have been used to probe solvent effects in mixtures of chloroform or dichloromethane with polar hydrogen-bond acceptors, such as DMSO. In these reactions, nucleophilic attack is rate limiting. Attempts to correlate reactivity with the empirical solvent... 

Because EHOMO is a measure of the ability of a compound to donate electrons (i.e., act as a nucleophilic species or undergo oxidation), the increase in kinetic rate leads to increasing destruction efficiency. In the case of activation energy, activation energy increases as EHOMO decreases therefore, EHOmo is 311 indicator of the ability of the aliphatic compound to donate electrons. Muller and Klein (1991) studied a set of 63 aliphatic compounds, and they stated that the reaction rate was significantly correlated with the Ehomo-... 

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