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Generation of TiII Alkyne Trimerization Catalysts in the Absence of Strong Metal Reductants.

ABSTRACT: Low-valent TiII species have typically been synthesized by the reaction of TiIV halides with strong metal reductants. Herein we report that TiII species can be generated simply by reacting TiIV imido complexes with 2 equiv of alkyne, yielding a metallacycle that can reductively eliminate pyrrole while liberating TiII. In order to probe the generality of this process, TiII-catalyzed alkyne trimerization reactions were carried out with a diverse range of TiIV precatalysts.

SUBMITTER: See XY

PROVIDER: S-EPMC5497852 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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Generation of TiII Alkyne Trimerization Catalysts in the Absence of Strong Metal Reductants.

See Xin Yi XY Beaumier Evan P EP Davis-Gilbert Zachary W ZW Dunn Peter L PL Larsen Jacob A JA Pearce Adam J AJ Wheeler T Alex TA Tonks Ian A IA

Organometallics 20170329 7

Low-valent TiII species have typically been synthesized by the reaction of TiIV halides with strong metal reductants. Herein we report that TiII species can be generated simply by reacting TiIV imido complexes with 2 equiv of alkyne, yielding a metallacycle that can reductively eliminate pyrrole while liberating TiII. In order to probe the generality of this process, TiII-catalyzed alkyne trimerization reactions were carried out w ...[more]

PMID: 28690352

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