(S)-[4-(Pyridin-4-yl)-4,5-dihydro-3H-dinaphtho[2,1-c:1',2'-e]azepine-2,6-diyl]bis[bis[4-(tert-butyl)phenyl]methanol]

These asymmetric organocatalysts [P2380] and [P2617] are novel chiral DMAP derivatives, developed by Mandai and Suga et al.¹⁾ They show extremely high catalytic activity (0.1-0.5 mol % catalyst) and enantioselectivity in chiral acylating reactions, such as Steglich rearrangements¹⁾, the kinetic resolution of secondary carbinols²⁾ and D,L-1,2-diols³⁾, and the desymmetrization of meso-1,2-diols.⁴⁾

Typical Procedure(Steglich rearrangement,¹⁾ R=CH₃):
To a solution of phenyl 2-((phenoxycarbonyl)oxy)-3-methyl-1H-indole-1-carboxylate (37.4 mg, 0.1 mmol) in THF (0.25 mL) is added a solution of the DMAP chiral analog [P2380] (0.48 mg, 0.5 µmol) in THF at -20 °C. The reaction mixture was stirred for 5 h at -20 °C and then 1 M aqueous HCl is added. The resulting mixture is extracted with EtOAc, dried over MgSO₄ and concentrated in vacuo. The purification of the crude product by flash column chromatography on a short pad of silica gel (eluent: hexane/Et₂O = 1/1) gives (S)-diphenyl 3-methyl-2-oxoindoline-1,3-dicarboxylate (36.9 mg, 99% yield).