A visible-light Paternò–Büchi dearomatisation process towards the construction of oxeto-indolinic polycycles. Issue 25 (29th April 2020)

• Record Type: Journal Article
• Authors: Mateos, Javier; Vega-Peñaloza, Alberto; Franceschi, Pietro; Rigodanza, Francesco; Andreetta, Philip; Companyó, Xavier; Pelosi, Giorgio; Bonchio, Marcella; Dell'Amico, Luca
• Is Part Of: Chemical science. Volume 11:Issue 25(2020)
• Page Start: 6532
• Page End: 6538
• Publication Date: 2020-04-29
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/d0sc01569e
• Languages: English
• ISSNs: 2041-6520

Abstract

Abstract : A scalable visible-light [2 + 2]-heterocycloaddition process allows the dearomatisation of indoles to complex biorelevant 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.