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US 5,395,992 AGranted
Synthesis of diols, for use as intermediates for polymeric materials, by starting from terminal diolefins
AssigneeEnichem S.p.A.
InventorsMarco Ricci, Francesco Gementi, Francesco Panella, Cecilia Querci, Raffaele Ungarelli
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Abstract
Disclosed is the synthesis of terminal diols, which are organic intermediates used in order to produce polymeric materials, by starting from terminal diolefins, which synthesis is based on the oxidation of diolefins to yield diepoxides, in a double-phase aqueous-organic system with hydrogen peroxide and in the presence of catalysts soluble in the organic phase, followed by a reaction of reduction of the resulting diepoxides.
Claims6
A process for preparing a .alpha., .omega.-diol of formula (I):
- HO--(CH.sub.2).sub.n --OH
- which comprises:
- epoxidizing both double bonds of an .alpha., .omega.-diene of formula (II):
- CH.sub.2 .dbd.CH--(CH.sub.2).sub.n-4 --CH.dbd.CH.sub.2
- wherein n.gtoreq.8 with from 1.8 to 4 moles of hydrogen peroxide, per mole of diolefin starting material, in a double phase, aqueous-organic system in the presence of a catalyst, which is soluble in the organic phase, constituted of a tetraalkylammonium phosphotungstate at a temperature ranging from 40.degree. to 90.degree. C., thereby forming a diepoxide of formula (III):
- ##STR2## wherein n is as defined above;
- (b) separating the diepoxide, which has been prepared, from its reaction medium;
- and
- (c) regioselectively hydrogenating both epoxide groups of diepoxide (III) in a solvent medium at a temperature not greater than 100.degree. C. under a hydrogen pressure ranging from 2 to 5 atm in the presence of a heterogeneous Raney nickel hydrogenation catalyst.
6 more elements
Dependencies are inferred from the claim text.