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Stereodivergent access to all four stereoisomers of chiral tetrahydrobenzo[f][1,4]oxazepines, through highly diastereoselective multicomponent Ugi-Joullie reaction.

ABSTRACT: Starting from easily accessible chiral enantiopure 1,2-amino alcohols and salicylaldehydes, a concise route to cyclic imines has been developed. These chiral cyclic imines undergo a highly diastereoselective Ugi-Joullié reaction to give trans tetrahydrobenzo[f][1,4]oxazepines with the introduction of up to 4 diversity inputs. The cis isomer may also be attained, thanks to a thermodynamically controlled base catalysed epimerization. Free secondary amines have been obtained using an unprecedented "removable" carboxylic acid.

SUBMITTER: Pinna A

PROVIDER: S-EPMC9047508 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Stereodivergent access to all four stereoisomers of chiral tetrahydrobenzo[f][1,4]oxazepines, through highly diastereoselective multicomponent Ugi-Joullié reaction.

Pinna Alessandro A Basso Andrea A Basso Andrea A Lambruschini Chiara C Moni Lisa L Riva Renata R Rocca Valeria V Banfi Luca L

RSC advances 20200103 2

Starting from easily accessible chiral enantiopure 1,2-amino alcohols and salicylaldehydes, a concise route to cyclic imines has been developed. These chiral cyclic imines undergo a highly diastereoselective Ugi-Joullié reaction to give trans tetrahydrobenzo[f][1,4]oxazepines with the introduction of up to 4 diversity inputs. The cis isomer may also be attained, thanks to a thermodynamically controlled base catalysed epimerization. Free secondary amines have been obtained us ...[more]

PMID: 35494435

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