sodium t-butanolate; (R)-1,1'-binaphthalene-2,2'-diol lithium salt in tetrahydrofuran T=20 - 25°C; Michael addition; 72 h;

benzene

diethyl ether; ethanol

ethanol

ethanol

ethanol

(i) Zn, Et2O, (ii) /BRN= 1773932/; Multistep reaction;

1: 1.) NaH / 1.) dimethoxyethane, 1 h, 2.) dimethoxyethane, overnight 2: 81 percent / 1.) aq.NaOH, 2.) 4 M HCl / 1.) 100 deg C, 10 h, 2.) 150-160 deg C, 4 h, 3: 81 percent / Na / toluene / 0.5 h / 110 °C 4: 1.) 57percent phosphoric acid, 2.) p-toluenesulfonic acid / 1.) 60 deg C, 3 h, 2.) DMF, 60 deg C, 20 h View Scheme

1: 1.) NaH, 2.)hexamethylphosphoric triamide / 1.) 1,2-dimethoxyethane, 1 h, 2.) 1,2-dimethoxyethane 2: 84 percent / 1.) aq.NaOH, 2.) 4 M HCl / 1.) 100 deg C, 10 h, 2.) 150-160 deg C, 4 h, 3: 85 percent / Na / toluene / 0.5 h / 110 °C 4: 74 percent / 57percent H3PO4 / 3 h / 50 - 60 °C View Scheme