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Efficient catalytic alkyne metathesis with a fluoroalkoxy-supported ditungsten(III) complex.

ABSTRACT: The molybdenum and tungsten complexes M₂(OR)₆ (Mo2F6, M = Mo, R = C(CF₃)₂Me; W2F3, M = W, R = OC(CF₃)Me₂) were synthesized as bimetallic congeners of the highly active alkyne metathesis catalysts [MesC?M{OC(CF₃) _n Me_3- _n }] (MoF6, M = Mo, n = 2; WF3, M = W, n = 1; Mes = 2,4,6-trimethylphenyl). The corresponding benzylidyne complex [PhC?W{OC(CF₃)Me₂}] (W ^Ph F3) was prepared by cleaving the W?W bond in W2F3 with 1-phenyl-1-propyne. The catalytic alkyne metathesis activity of these metal complexes was determined in the self-metathesis, ring-closing alkyne metathesis and cross-metathesis of internal and terminal alkynes, revealing an almost equally high metathesis activity for the bimetallic tungsten complex W2F3 and the alkylidyne complex W ^Ph F3. In contrast, Mo2F6 displayed no significant activity in alkyne metathesis.

SUBMITTER: Ehrhorn H

PROVIDER: S-EPMC6178283 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Efficient catalytic alkyne metathesis with a fluoroalkoxy-supported ditungsten(III) complex.

Ehrhorn Henrike H Schlösser Janin J Bockfeld Dirk D Tamm Matthias M

Beilstein journal of organic chemistry 20180918

The molybdenum and tungsten complexes M2(OR)6 (Mo2F6, M = Mo, R = C(CF3)2Me; W2F3, M = W, R = OC(CF3)Me2) were synthesized as bimetallic congeners of the highly active alkyne metathesis catalysts [MesC≡M{OC(CF3) n Me3- n }] (MoF6, M = Mo, n = 2; WF3, M = W, n = 1; Mes = 2,4,6-trimethylphenyl). The corresponding benzylidyne complex [ ...[more]

PMID: 30344767

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