TY - JOUR A1 - Zaghi, Anna A1 - Ragno, Daniele A1 - Di Carmine, Graziano A1 - De Risi, Carmela A1 - Bortolini, Olga A1 - Giovannini, Pier Paolo A1 - Fantin, Giancarlo A1 - Massi, Alessandro T1 - Electron-transfer-initiated benzoin- and Stetter-like reactions in packed-bed reactors for process intensification JF - Beilstein Journal of Organic Chemistry PY - 2016/// VL - 12 SP - 2719 EP - 2730 SN - 1860-5397 DO - 10.3762/bjoc.12.268 PB - Beilstein-Institut JA - Beilstein J. Org. Chem. UR - https://doi.org/10.3762/bjoc.12.268 KW - C–C coupling KW - continuos-flow KW - diketone KW - electron-transfer KW - umpolung N2 - A convenient heterogeneous continuous-flow procedure for the polarity reversal of aromatic α-diketones is presented. Propaedeutic batch experiments have been initially performed to select the optimal supported base capable to initiate the two electron-transfer process from the carbamoyl anion of the N,N-dimethylformamide (DMF) solvent to the α-diketone and generate the corresponding enediolate active species. After having identified the 2-tert-butylimino-2-diethylamino-1,3-dimethylperhydro-1,3,2-diazaphosphorine on polystyrene (PS-BEMP) as the suitable base, packed-bed microreactors (pressure-resistant stainless-steel columns) have been fabricated and operated to accomplish the chemoselective synthesis of aroylated α-hydroxy ketones and 2-benzoyl-1,4-diones (benzoin- and Stetter-like products, respectively) with a good level of efficiency and with a long-term stability of the packing material (up to five days). ER -