Back to results
US 6,147,251 AGranted
Process for the preparation and uses of derivatives of esters of .alpha.-methylene-.beta.-hydroxy acids
AssigneeUniroyal Chemical Company, Inc.
InventorsXu Wu Feng, Walter Nudenberg
Life of this patent
Estimating the term…
Abstract
A process for the preparation of derivatives of halo-but-2-enoic acids and esters high in 2-ene content, several of which are novel. The esters and their derivatives are useful as promoters for the polymerization of ethylene or the copolymerization of ethylene with .alpha.-olefins and, optionally, nonconjugated polyenes. The promoters can also be combined with transition metal compounds, e.g., vanadium, to form combination promoter-catalyst compounds.
Claims5
A process for the preparation of compounds of the formula:
- ##STR16## from an ester of the formula:
- ##STR17## wherein R.sub.1 is selected from the group consisting of hydrogen, alkyl, alkaryl, aralkyl, haloalkyl, haloaryl, haloalkaryl, haloaralkyl, alkenyl, cycloalkyl, amino, xanthanyl, sulfinyl, sulfonyl, aryl, acyl, oxyalyl, and aroyl;
- and
- R.sub.5 is selected from the group consisting of hydrogen, alkyl, alkaryl, aralkyl, haloalkyl, haloaryl, haloalkaryl, haloaralkyl, alkenyl, cycloalkyl, aryl, xanthanyl, sulfinyl, sulfonyl, aryl, acyl, oxyalyl, and aroyl;
- wherein the process comprises reacting said ester with:
- A) at least one Lewis acid or base and, optionally, a stoichiometric amount of mild hydride in the absence of a transition metal catalyst, or
- B) hydrogen in the presence of a catalyst selected from the group consisting of transition metals or their oxides to form at least one intermediate and then reacting said at least one intermediate with a mild base in a catalytic to stoichiometric amount.
4 more elements
Dependencies are inferred from the claim text.