in tetrahydrofuran; diethyl ether T=20°C; Grignard addition; 12 h;

1.1: 90 percent / tetrahydrofuran; diethyl ether / 12 h / 20 °C 2.1: BH3*DMS / tetrahydrofuran / 12 h / 20 °C 2.2: aq. NaOH; aq. H2O2; EtOH / tetrahydrofuran / 2 h / 20 °C 2.3: 70 percent / DIAD; PPh3 / tetrahydrofuran / 0 - 20 °C View Scheme