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Combining silver- and organocatalysis: an enantioselective sequential catalytic approach towards pyrano-annulated pyrazoles.

ABSTRACT: A one-pot asymmetric Michael addition/hydroalkoxylation sequence, catalyzed by a sequential catalytic system consisting of a squaramide and a silver salt, provides a new series of chiral pyrano-annulated pyrazole derivatives in excellent yields (up to 95%) and high enantioselectivities (up to 97% ee).

SUBMITTER: Hack D

PROVIDER: S-EPMC4611987 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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Combining silver- and organocatalysis: an enantioselective sequential catalytic approach towards pyrano-annulated pyrazoles.

Hack Daniel D Chauhan Pankaj P Deckers Kristina K Mizutani Yusuke Y Raabe Gerhard G Enders Dieter D

Chemical communications (Cambridge, England) 20150201 12

A one-pot asymmetric Michael addition/hydroalkoxylation sequence, catalyzed by a sequential catalytic system consisting of a squaramide and a silver salt, provides a new series of chiral pyrano-annulated pyrazole derivatives in excellent yields (up to 95%) and high enantioselectivities (up to 97% ee). ...[more]

PMID: 25564304

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