Microfluidic light-driven synthesis of tetracyclic molecular architectures.
Herein we report an effective synthetic method for the direct assembly of highly functionalized tetracyclic pharmacophoric cores. Coumarins and chromones undergo diastereoselective [4 + 2] cycloaddition reactions with light-generated photoenol intermediates. The reactions occur by aid of a microfluidic photoreactor (MFP) in high yield (up to >98%) and virtually complete diastereocontrol (>20:1 dr). The method is easily scaled-up to a parallel setup, furnishing 948 mg of product over a 14 h reaction time. Finally, a series of manipulations of the tetracyclic scaffold obtained gave access to valuable precursors of biologically active molecules.
['Mateos|Javier|J|0000-0002-2358-9183', 'Meneghini|Nicholas|N|0000-0003-1199-5624', 'Bonchio|Marcella|M|0000-0002-7445-0296', 'Marino|Nadia|N|0000-0002-7038-9715', 'Carofiglio|Tommaso|T|0000-0002-4648-1458', 'Companyó|Xavier|X|0000-0001-8969-7315', "Dell'Amico|Luca|L|0000-0003-0423-9628"]
cycloaddition microfluidic photoreactor [4 + 2] photoenol flow chemistry photoredox catalysis synthetic photochemistry