A Continuous-Flow, Two-Step, Metal-Free Process for the Synthesis of Differently Substituted Chiral 1,2-Diamino Derivatives

作者：Pirola Margherita; Compostella Maria Elena; Raimondi Laura; Puglisi Alessandra; Benaglia Maurizio

来源：Synthesis, 2018, 50(7): 1430-1438.

DOI：10.1055/s-0036-1591911

<jats:p>The enantioselective organocatalytic reduction of aryl-substituted nitroenamines was successfully performed under continuous-flow conditions. After a preliminary screening with a 10-μL microreactor, to establish the best reaction conditions, the reduction was scaled up in a 0.5-mL mesoreactor, without appreciable loss of enantioselectivity, that remained constantly higher than 90%. The in-flow nitro reduction was also accomplished, either by Raney nickel catalyzed hydrogenation or by a metal-free methodology based on the use of the very inexpensive and readily available reducing agent trichlorosilane. The final aim is to develop a two-step, continuous-flow process for the stereo­selective, metal-free, catalytic synthesis of differently functionalized chiral 1,2-diamines.</jats:p>

• 出版日期2018-4