Fig. 4: Synthetic applications.
From: Pyrinap ligands for enantioselective syntheses of amines
a Retrosynthetic analysis of (S)-6. b A catalytic enantioselective synthesis of (S)-(-)-N-acetylcolchinol (S)-6. c Transformation of propargylic amines (S)-4aaa and (S)-4aqa. Reagents and conditions: (i) Ni(OAc)2·4H2O (1 equiv), NaBH4 (1 equiv), ethylenediamine (3.5 equiv), EtOH, H2 (1 atm), r.t., 3 h; (ii) LiAlH4 (2 equiv), THF, 0 °C to r.t., 3 h; (iii) TBSCl (1.2 equiv), imidazole (2 equiv), DCM, r.t., 12 h; (iv) ZnI2 (50 mol%), toluene, 110 °C, 8 h; (v) TBAF·3H2O (1 equiv), THF, 0 °C to r.t., 12 h; (vi) phthalimide (1 equiv), DEAD (1.1 equiv), PPh3 (1 equiv), THF, 0 °C to r.t., 12 h. DCM dichloromethane, DEAD diethyl azodicarboxylate, DMAP 4-dimethylaminopyridine, DMC dimethyl carbonate, TBAF tetrabutylammonium fluoride, TBSCl tert-butyldimethylsilyl chloride, TFA trifluoroacetic acid, TFAA trifluoroacetic anhydride, THF tetrahydrofuran.
