1. A visible-light Paternò-Büchi dearomatisation process towards the construction of oxeto-indolinic polycycles
- Author
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Javier Mateos, Xavier Companyó, Marcella Bonchio, Francesco Rigodanza, Alberto Vega-Peñaloza, Pietro De Franceschi, Giorgio Pelosi, Philip Andreetta, and Luca Dell'Amico
- Subjects
Indole test ,Reaction mechanism ,Chemistry ,Yield (chemistry) ,Aromatic ketones ,General Chemistry ,Combinatorial chemistry ,Stereocenter ,Visible spectrum - 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., A scalable visible-light [2 + 2]-heterocycloaddition process allows the dearomatisation of indoles to complex biorelevant polycycles.
- Published
- 2021