PhotoRedOx Flow Reactor

Reaction Protocol:

In a 4–ml vial equipped with a Teflon septa were weighed NiCl2–dme (1.1 mg, 5 μmol, 5 mol %) and dtbbpy (1.3 mg, 5 μmol, 5 mol %). 1 ml of dry MeOH was added to the vial and the vial was stirred on an orbital shaker until complete dissolution. The solution was evaporated to dry at room temperature. Then Ir(dF–CF3–ppy)2(dtbpy) (1.1 mg, 1 μmol, 1 mol %), and 4–bromoacetophenone (9.95 mg, 100 μmol, 1 equiv.) were added. 1 ml of dry acetonitrile was added fol- lowed by Et3N (21 μmol, 300 μmol, 3 equiv.) and aniline (4.65 mg, 100 μmol, 1 equiv.). The solution was sparged with nitrogen via submerged needle for 5 minutes.

Several batches of 100 μl of solution were successively injected to the flow reactor placed in EvoluChem PhotoRedOx Box with blue Kessil LED using an injection module (Gilson) and the samples were circulated using a HLPC pump at different flow rates to allow residence time of 5, 10, 15, 20 and 30 min. Reaction completion was monitored by LC–MS using the ratio bromoacetophenone/product.