M. Krishna Pillay

Kinetics of reaction of triethylammonium carboxylates with α-halogenocarbonyl compounds in organic solvents : Reaction of benzoates and phenoxyacetates with phenacyl bromide in acetone

Abstract The kinetics of the reaction of phenacyl bromide with triethylammonium p-substituted benzoates and phenoxyacetates at 25°, 30° and 35° in acetone suggest a rigid cyclic transition state involving a hydrogen bonded ion-pair as the active nucleophile. The effect of addition of water on the rate constant is rationalized. Regression analysis on single parameter treatment on benzoates shows that the reaction obeys the Hammett equation (ϱ value + 0.37, with r = 0.993).

Kinetics of oxidation of fluorene by alkaline hexacyanoferrate(III)

The kinetics of oxidation of fluorene by alkaline hexacyanoferrate(III) is followed under pseudo-first-order conditions in 50% aqueous acetonitrile. The reaction is first-order both in the oxidant and substrate. The rate dependence on [NaOH] is unity. Hexacyanoferrate(II) retards the reaction. The product of oxidation is fluorenone and the stoichiometry between the substrate and the oxidation is 1:4. A large positive salt effect and specific cation effect are observed. A tentative mechanism accounting for all the observations is envisaged.

Crystal and molecular structure of 1-methyl-2,3,5,6-tetraphenylpiperidin-4-ol, C30H29NO

The structure of the the title compound, C30H29NO, was determined by X-rays.Mr=419.57, triclinic, space groupP1,a=5.8922(12),b=8.5855(11),c=12.2216(20) Å,α=78.145(12)°,β=79.181(15)°, γ=76.108(14)°,Vc=581.1(1) Å3,Z=1,Dx=1.199 Mg m−3. CuKα radiation (graphite crystal monochromator, λ=1.54184 Å),μ(CuKα)=5.17 cm−1,T=290K. Final conventionalR-factor=0.039,Rw=0.042 for 2795 observed reflections and 377 variables. The structure was solved usingMultan andDirdif. With a view to determining the conformational preference of the piperidine ring when it is highly sustituted with a bulky group like the phenyl group, the present X-ray investigation was undertaken.