Fig. 4: Catalytic enantioselective synthesis of bis- and tri-TBs.
From: Organocatalytic asymmetric synthesis of Tröger’s bases
Unless otherwise indicated, the reaction conditions were as follows: 1a (1.2(n + 1) equiv), 4 (0.1 mmol, 1 equiv), (ent)-C5 (5 mol%), 3 Å MS (100 mg) in CHCl3 (1 mL) at −40 °C for 24 h.
