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Titanium(III)-Catalyzed Reductive Decyanation of Geminal Dinitriles by a Non-Free-Radical Mechanism.

ABSTRACT: A titanium-catalyzed mono-decyanation of geminal dinitriles is reported. The reaction proceeds under mild conditions, tolerates numerous functional groups, and can be applied to quaternary malononitriles. A corresponding desulfonylation is demonstrated as well. Mechanistic experiments support a catalyst-controlled cleavage without the formation of free radicals, which is in sharp contrast to traditional stoichiometric radical decyanations. The involvement of two Ti^III species in the C-C cleavage is proposed, and the beneficial role of added ZnCl₂ and 2,4,6-collidine hydrochloride is investigated.

SUBMITTER: Weweler J

PROVIDER: S-EPMC6899653 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Titanium(III)-Catalyzed Reductive Decyanation of Geminal Dinitriles by a Non-Free-Radical Mechanism.

Weweler Jens J Younas Sara L SL Streuff Jan J

Angewandte Chemie (International ed. in English) 20191023 49

A titanium-catalyzed mono-decyanation of geminal dinitriles is reported. The reaction proceeds under mild conditions, tolerates numerous functional groups, and can be applied to quaternary malononitriles. A corresponding desulfonylation is demonstrated as well. Mechanistic experiments support a catalyst-controlled cleavage without the formation of free radicals, which is in sharp contrast to traditional stoichiometric radical decyanations. The involvement of two Ti<sup>III</sup> species in the C ...[more]

PMID: 31513329

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