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Platinum(II) Enyne Cycloisomerization Catalysis: Intermediates and Resting States.

ABSTRACT: In situ generated [(PPP)Pt][BF(4)](2) (PPP = triphos) catalyzes the cycloisomerization of 1,6-enyne-ols by initiative pi-activation of the alkyne. This generates an isolable cationic Pt-alkenyl species which subsequently participates in turnover limiting protonolysis with in situ generated acid. This latter reactivity contrasts cationic Pt-alkyls which are more difficult to protonolyze. Mechanistic studies on isolated Pt-alkenyls, and deuterium labeling helped to elucidate the mechanistic details.

SUBMITTER: Nelsen DL

PROVIDER: S-EPMC2662608 | biostudies-literature | 2009 Feb

REPOSITORIES: biostudies-literature

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Platinum(II) Enyne Cycloisomerization Catalysis: Intermediates and Resting States.

Nelsen D Luke DL Gagné Michel R MR

Organometallics 20090201 4

In situ generated [(PPP)Pt][BF(4)](2) (PPP = triphos) catalyzes the cycloisomerization of 1,6-enyne-ols by initiative pi-activation of the alkyne. This generates an isolable cationic Pt-alkenyl species which subsequently participates in turnover limiting protonolysis with in situ generated acid. This latter reactivity contrasts cationic Pt-alkyls which are more difficult to protonolyze. Mechanistic studies on isolated Pt-alkenyls, and deuterium labeling helped to elucidate the mechanistic detail ...[more]

PMID: 20160853

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