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Exploring the Reactivity of Na[W2(?-Cl)3Cl4(THF)2]?(THF)3 towards the Polymerization of Selected Cycloolefins.

ABSTRACT: The bimetallic compound Na[W2(?-Cl)3Cl4(THF)2]·(THF)? (1, {W (3) W}(6+), a'2e'4) is a highly efficient room-temperature initiator for ring opening metathesis polymerization (ROMP) of norbornene (NBE) and some of its derivatives. In most cases, addition of phenylacetylene (PA) as co-initiator improves the catalytic activity and retains the high cis-stereoselectivity. On the other hand, 1 can polymerize cyclopentadiene (CPD), not via a metathetic, but rather, via a cationic mechanism. Here, we present a comparison of the reactivity of the two catalytic systems (1 and 1/PA) between themselves and with other systems reported in the literature, the characterization of the polymers formed and mechanistic aspects of the corresponding reactions.

SUBMITTER: Saragas N

PROVIDER: S-EPMC6332418 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature

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Exploring the Reactivity of Na[W2(μ-Cl)3Cl4(THF)2]∙(THF)3 towards the Polymerization of Selected Cycloolefins.

Saragas Nikolaos N Floros Georgios G Raptopoulos Grigorios G Pitsikalis Marinos M Paraskevopoulou Patrina P Mertis Konstantinos K

Molecules (Basel, Switzerland) 20151208 12

The bimetallic compound Na[W2(μ-Cl)3Cl4(THF)2]·(THF)₃ (1, {W (3) W}(6+), a'2e'4) is a highly efficient room-temperature initiator for ring opening metathesis polymerization (ROMP) of norbornene (NBE) and some of its derivatives. In most cases, addition of phenylacetylene (PA) as co-initiator improves the catalytic activity and retains the high cis-stereoselectivity. On the other hand, 1 can polymerize cyclopentadiene (CPD), not via a metathetic, but rather, via a cationic mechanism. Here, we pre ...[more]

PMID: 26670223

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