lithium tri-t-butoxyaluminum hydride in diethylene glycol dimethyl ether T=-76°C; 0.5 h;

1: 94 percent / SOCl2 / benzene / 0.5 h / Heating 2: 79 percent / LiAlH(OBu-t)3 / bis-(2-methoxy-ethyl) ether / 0.5 h / -76 °C View Scheme

1: 9H-xanthene With n-butyllithium in tetrahydrofuran; n-heptane T=-65°C; 0.5 h; 2: formic acid ethyl ester in tetrahydrofuran; n-heptane T=-70°C; 3 h;