Studies on the Decomposition of Alkyl Hydroperoxides by different catalysts

Abstract

The catalytic decomposition of cumene, 1‐methylcyclohexyl and cyclohexyl hydroperoxides was studied in cyclohexane, cis‐ and trans‐1,4‐dimethylcyclohexane and cis‐pinane as the solvents. The stearates and the acetylacetonates of manganese, cobalt and chromium, the acetylacetonates of molybdenum and vanadium, n‐butyl orthoborate and n‐butyl metaborate were used as the catalysts. The chromium‐, vanadium‐, molybdenum‐ and boron‐containing catalysts brought about some Hock‐type decomposition of cumene hydroperoxide and thus proved to be acidic. Of these more of less acidic catalysts only molybdenyl acetylacetonate effected a partially stereospecific hydroxylation of the tertiary CH‐bonds in cis‐ and trans‐1,4‐dimethylcyclohexane. The well‐known selectivity of chromium catalysts for the ketone formation during the decomposition of secondary hydroperoxides is caused by the catalytic oxidatio of secondary alcohols by hydroperoxides in the presence of chromium compounds. In the presence of all the catalysts used the free‐radical pathways of the hydroperoxide decomposition predominated, and the attack of the intermediate radicals on the starting hydroperoxide was more important than the attack on the solvent molecules.

Unified Catalytic Oxidation–Adsorption Desulfurization Process Using Cumene Hydroperoxide as Oxidant and Vanadate Based Polyionic Liquid as Catalyst and Sorbent

“…All the oil samples were analyzed by HPLC and the spectra are compared in Figure . It is noted that the peaks of DBT and CHP virtually disappear after the oxidation reaction along with the increased peaks of octanones, 2-phenyl-2-propanol, acetophenone, and α-methylstyrene, resulting from the oxidized of octane, as well as the reduction and decomposition of CHP catalyzed by vanadate . Thus, the CHP amount needs to be excessive.…”

Chromium-catalyzed oxidations in organic synthesis

“…Chromium esters have often been examined with the objective of obtaining catalysts soluble in organic media With this aim, a cheap fatty acid has been generally employed for the ester part, the catalyst most considered being chromium(III) stearate. 37,84,85,100,108,[117][118][119][120][121][122][123][124][125][126][127][128][129][130][131][132][133][134] The efficiency of chromium(III) acetate has been less in-vestigated37,88,106,134-141 while chromium(III) trifluoroacetate,134 chromium(III) naphthenate,108,142-145 and chromium(III) octoate146 have been rarely used.…”

“…)(H20)2C1 [8/0.66/0.1] CH2C12-H20, 26 °C, Cr(salen)(H20)2C1 [8/0.66/0.1] CH2C12-H20, 26 °C, 7 h sodium hypochlorite )Cl [1/7/0.025] R4NC1, CH2C12-H20, RT, 3 h (C 24)Y 8 See section VIII for the definitions for the abbreviations and symbols. 99, (exo/endo: 32) Cr(salen)(H20)2Cl [1/0.2/0.02] H20, RT, 5 h Y/O 21 as above + /3-cyclodextrin (0.03 equiv) Y/O 40 as above + 4-methylpyridine (0.06 equiv) Y/O 44 Cr(salen)(H20)2PF6 + pyridine (0.015 equiv) [1/0.03/0.005] CH2C12, RT Y/O 82Cr(m-salen)OTf + N-pyridine oxide (0.005 equiv) [1/0.05/0.01] MeCN, 25 "C Y/O85, exo CrO(m-salen)(OTf) + JV-pyridine oxide (0-0.4 equiv) [1/0.5/0.1] MeCN, 25 "C pentafiuoroiodosylbenzene Y/O[70][71][72][73][74][75][76][77][78][79][80][81][82][83][84][85] …”

Studies on the Oxidation of Phenyl Cycloalkanes by tertiary hydroperoxides

“…Some time ago we st utlietl the deconiposit ion of cuniene, I-niethylcyclohexyl and cyclohexyl hydroperoxides in different hydrocarbons as solvents and found 20 -3O"C, (11 ith regartl to the tlccomposetl hydroperoxide) of ouitlatioii products of the solvent hydrocarbons [ 11. The attack at tlie liytlrocarbon solvents obviously proceeded via free radicals. Only in the decompositioiis in the presence of niolybdenyl acet.vlacetotiate did an S,,2 attack at cis-and tmns-l,4-tliniethyl cyclohexane talw place [l].…”