84633-54-5Relevant articles and documents
Transesterification of methyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propanoate with tetrakis(hydroxymethyl)methane. the properties of the reaction products
Volod'Kin,Zaikov,Evteeva
, p. 1689 - 1693 (2013/11/19)
The transesterification of methyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propanoate with tetrakis(hydroxymethyl)methane depends on the equilibrium constants of the reversible reactions; for the final step, the equilibrium constant is K 1. The molecular geometries and the enthalpies and entropies of the equilibrium reactions were calculated by the semiempirical PM6 quantum chemical method. The thermodynamic equilibrium constants of the reversible reactions were calculated by the Boltzmann equation from the Gibbs energies G f ○. For tris-[3-(3,5-di-tert-butyl-4-hydroxyphenyl) propanoyloxymethyl](hydroxymethyl)methane, the dipole moment is μ = 0.97 D and the energy of the O-H homolysis is D OH = 347.3 kJ mol -1. For tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl) propanoyloxymethyl]methane, μ is 5.6 D and D OH is 321 kJ mol -1. The geometry of the structure affects the H-O homolysis energy and the chain termination coefficient under the conditions of inhibited cumene oxidation.
PREPARATION OF TETRAKIS [3-(E,5-DI-TERT-BUTYL-4-HYDROXY PHENYL) PROPIONYL OXYMETHYL] METHANE
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Page/Page column 4-6, (2008/06/13)
A transesterification process for the preparation of tetrakis [3-(3,5-di-tert-butyl-4hydroxy phenyl) propionyl oxymethyl] methane by the reaction of methyl-(3,5-di-tertbutyl-4-hydroxy phenyl) propionate ester with pentaerythritol wherein the reaction takes place in the presence of an ester exchange catalyst combination consisting of (a) at least one basic or neutral catalyst and (b) at least one metal compound capable of behaving as a Lewis acid and wherein the reaction is conducted through a first stage in which only basic or neutral catalyst is present in the reaction mixture followed by a second stage which commences with the addition of Lewis acid catalyst to the reaction mixture when the amount of di-substituted intermediate product contained within the reaction mixture is less than 20 area % analysed by HPLC. The preferred basic catalysts are lithium hydroxide and lithium hydroxide monohydrate. The preferred Lewis acid catalyst is zinc octanoate.