Kinetic studies nucleophilic aliphatic substitution

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... 

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

K. Okamoto, S. Fukui, I. Nitta, and H. Shingu, Bull. Chem. Soc. Jpn., 40, 2354 (1967). Kinetic Studies of Bimolecular Nucleophilic Substitution. VIll. The Effect of Hydroxylic Solvents on the Nucleophilicity of Aliphatic Amines in the Menschutkin Reaction. 

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... 

Competitive effects for the interactions of cisplatin with various active sites in the cellular environment are discussed in papers of Deubel.55,56 In the earlier paper, energetic and structural data of complexes with the different substituted ligands were explored. The more recent work deals with kinetic factors in the relation to the transition state (TS) for water replacement of the semihydrated cisplatin complex (cis-[Pt(NH3)2(H20)Cl]+ ) with either an N- or S-containing ligand (thiopheneimidazol, dimethyl sulphide, or methanethiolate which serve as amino acid models). Deubel concluded the kinetic preference of N-sites over S-nucleophiles where the important role is played by the electrostatic terms. In addition, the aliphatic/aromatic character of the substituent as well as the influence of different dielectric constants of the environment are very important. A more realistic model for the aqua-ligand replacement with adenine and guanine was studied in works of Chval et al.53,57 and Eriksson and coworkers.58 They performed independently the estimation of the thermodynamic and kinetic parameters of this process. 

The first kinetic investigation of a nucleophilic substitution reaction was that of Werner et who studied the reaction of 11 with several primary aliphatic... 

In addition, the same group has studied the ability to use aliphatic alcohols as competent nucleophiles in the Pd-catalysed dynamic kinetic asymmetric transformation of Baylis Hillman adducts. The corresponding substituted pyran products were obtained in high yields and enantioselectivities, as shown in Scheme 2.55. The utility of this method was further demonstrated in the context of concise total syntheses of the gastrulation inhibitor, (-l-)-hippo-spongic acid A, and the antibiotics, furaquinocins A, B and E. 

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