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A visible-light Paterno-Buchi dearomatisation process towards the construction of oxeto-indolinic polycycles.

ABSTRACT: A variety of highly functionalised N-containing polycycles (35 examples) are synthesised from simple indoles and aromatic ketones through a mild visible-light Paternò-Büchi process. Tetrahydrooxeto[2,3-b]indole scaffolds, with up to three contiguous all-substituted stereocenters, are generated in high yield (up to >98%) and excellent site- regio- and diastereocontrol (>20 : 1). The use of visible light (405 or 465 nm) ensures enhanced performances by switching off undesired photodimerisation side reactions. The reaction can be easily implemented using a microfluidic photoreactor with improved productivity (up to 0.176 mmol h^-1) and generality. Mechanistic investigations revealed that two alternative reaction mechanisms can account for the excellent regio- and diastereocontrol observed.

SUBMITTER: Mateos J

PROVIDER: S-EPMC8159410 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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A visible-light Paternò-Büchi dearomatisation process towards the construction of oxeto-indolinic polycycles.

Mateos Javier J Vega-Peñaloza Alberto A Franceschi Pietro P Rigodanza Francesco F Andreetta Philip P Companyó Xavier X Pelosi Giorgio G Bonchio Marcella M Dell'Amico Luca L

Chemical science 20200416 25

A variety of highly functionalised N-containing polycycles (35 examples) are synthesised from simple indoles and aromatic ketones through a mild visible-light Paternò-Büchi process. Tetrahydrooxeto[2,3-b]indole scaffolds, with up to three contiguous all-substituted stereocenters, are generated in high yield (up to >98%) and excellent site- regio- and diastereocontrol (>20 : 1). The use of visible light (405 or 465 nm) ensures enhanced performances by switching off undesired ...[more]

PMID: 34094119

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