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Formal [4 + 1] cycloaddition of in situ generated 1,2-diaza-1,3-dienes with diazo esters: facile approaches to dihydropyrazoles containing a quaternary center.

ABSTRACT: A Cu(ii)/bisoxazoline ligand-promoted formal [4 + 1] cycloaddition of diazo esters with azoalkenes formed in situ has been developed. This strategy provides a potential protocol for the construction of dihydropyrazoles containing a quaternary center with good to excellent yields.

SUBMITTER: Chen B

PROVIDER: S-EPMC9059575 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Formal [4 + 1] cycloaddition of in situ generated 1,2-diaza-1,3-dienes with diazo esters: facile approaches to dihydropyrazoles containing a quaternary center.

Chen Bo B Chu Wen-Dao WD Liu Quan-Zhong QZ

RSC advances 20190111 3

A Cu(ii)/bisoxazoline ligand-promoted formal [4 + 1] cycloaddition of diazo esters with azoalkenes formed in situ has been developed. This strategy provides a potential protocol for the construction of dihydropyrazoles containing a quaternary center with good to excellent yields. ...[more]

PMID: 35518004

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