hexafluoroisopropyl alcohol; perfluoro-octylsulphonic acid in water T=90°C; Pictet-Spengler reaction; 18 h;

1: 6,7-dimethoxy-3,4-dihydro-1H-isochromene With 2,3-dicyano-5,6-dichloro-p-benzoquinone; bis-[(trifluoroacetoxy)iodo]benzene in 1,2-dichloro-ethane T=80°C; 3 h; Inert atmosphere; 2: PhMgI in diethyl ether; 1,2-dichloro-ethane T=-20°C; 3 h; Inert atmosphere;

1: CrO3; H2SO4 / acetone; H2O / 5 °C 2: NH2NH2*H2O / ethanol / Heating View Scheme