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Catalyst-Switchable Regiocontrol in the Direct Arylation of Remote C-H Groups in Pyrazolo[1,5-a]pyrimidines.

ABSTRACT: The regiodivergent palladium-catalyzed C-H arylation of pyrazolo[1,5-a]pyrimidine has been achieved, wherein the switch in regioselectivity between positions C3 and C7 is under complete catalyst control. A phosphine-containing palladium catalyst promotes the direct arylation at the most acidic position (C7), whereas a phosphine-free catalyst targets the most electron-rich position (C3).

SUBMITTER: Bedford RB

PROVIDER: S-EPMC4531820 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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Catalyst-Switchable Regiocontrol in the Direct Arylation of Remote C-H Groups in Pyrazolo[1,5-a]pyrimidines.

Bedford Robin B RB Durrant Steven J SJ Montgomery Michelle M

Angewandte Chemie (International ed. in English) 20150610 30

The regiodivergent palladium-catalyzed C-H arylation of pyrazolo[1,5-a]pyrimidine has been achieved, wherein the switch in regioselectivity between positions C3 and C7 is under complete catalyst control. A phosphine-containing palladium catalyst promotes the direct arylation at the most acidic position (C7), whereas a phosphine-free catalyst targets the most electron-rich position (C3). ...[more]

PMID: 26095315

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