sodium tetrahydroborate; cobalt(II) chloride in tetrahydrofuran; water 48 h; Ambient temperature;

1: 1.) LDA, 2.) HMPA / 1.) THF, -78 deg C, 45 min, 2.) THF, RT, overnight 2: 81 percent / CoCl2*6H2O, NaBH4 / tetrahydrofuran; H2O / 48 h / Ambient temperature View Scheme