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Site-Selective Reaction of Enaminones and Enamine Esters for the Synthesis of Novel Diverse Morphan Derivatives.

ABSTRACT: An efficient and concise protocol was developed for the synthesis of diverse morphan derivatives 5-7 by the Michael and aza-Michael reaction of different types of quinone monoketals 1 or quinone imine ketals 2 with enaminones or enamine esters 3 promoted by 1,8-diazabicyclo[5.4.0]undec-7-ene in acetone at reflux. Notably, when cyclic enaminone 4 was used as a substrate in the aza-Michael and 1,2-addition reactions with quinone monoketals 1, they gave another novel morphan 8. This method is suitable for parallel synthesis of bridged ring compounds. As a result, highly diverse morphan derivatives were easily and efficiently prepared by the Michael/aza-Michael or aza-Michael/1,2-addition reactions.

SUBMITTER: Hu XM

PROVIDER: S-EPMC6644497 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Site-Selective Reaction of Enaminones and Enamine Esters for the Synthesis of Novel Diverse Morphan Derivatives.

Hu Xing-Mei XM Zhou Bei B Yang Chang-Long CL Lin Jun J Yan Sheng-Jiao SJ

ACS omega 20180604 6

An efficient and concise protocol was developed for the synthesis of diverse morphan derivatives 5-7 by the Michael and aza-Michael reaction of different types of quinone monoketals 1 or quinone imine ketals 2 with enaminones or enamine esters 3 promoted by 1,8-diazabicyclo[5.4.0]undec-7-ene in acetone at reflux. Notably, when cyclic enaminone 4 was used as a substrate in the aza-Michael and 1,2-addition reactions with quinone monoketals 1, they g ...[more]

PMID: 31458790

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