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General and Efficient Copper-Catalyzed Oxazaborolidine Complex in Transfer Hydrogenation of Isoquinolines under Mild Conditions.

ABSTRACT: A general and efficient method for copper-catalyzed transfer hydrogenation of isoquinolines with an oxazaborolidine-BH3 complex, under mild reaction conditions, is successfully developed. A broad range of isoquinolines has been reduced to the corresponding products with 61-85% yields. The method is applied to the synthesis of biologically active tetrahydrosioquinoline alkaloid (±)-norlaudanosine in 62% yield, which is the key precursor for the preparation of (±)-laudanosine, (±)-N-methyl-laudanosine, and (±)-xylopinine in one or two steps.

SUBMITTER: Du Q

PROVIDER: S-EPMC7450644 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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General and Efficient Copper-Catalyzed Oxazaborolidine Complex in Transfer Hydrogenation of Isoquinolines under Mild Conditions.

Du Qianyu Q Liu Linpeng L Zhou Taigang T

ACS omega 20200813 33

A general and efficient method for copper-catalyzed transfer hydrogenation of isoquinolines with an oxazaborolidine-BH3 complex, under mild reaction conditions, is successfully developed. A broad range of isoquinolines has been reduced to the corresponding products with 61-85% yields. The method is applied to the synthesis of biologically active tetrahydrosioquinoline alkaloid (±)-norlaudanosine in 62% yield, which is the key precursor for the preparation of (±)-laudanosine, (±)-N< ...[more]

PMID: 32875258

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