1: 99 percent / sodium hydroxide / methanol; H2O / 48 h 2: 83 percent / sodium carbonate, sodium tungstate, 40percent peracetic acid / H2O; methanol 3: 91 percent / 1) sodium methoxide, 2) sodium borohydride / methanol / 1) -30 degC, 20min, 2) 25 degC, 6h 4: 84 percent / paraformaldehyde, boron trifluoride etherate / H2O; acetone / 120 h / Ambient temperature View Scheme

1: 99 percent / sodium hydroxide / methanol; H2O / 48 h 2: 83 percent / sodium carbonate, sodium tungstate, 40percent peracetic acid / H2O; methanol 3: 91 percent / 1) sodium methoxide, 2) sodium borohydride / methanol / 1) -30 degC, 20min, 2) 25 degC, 6h 4: 11 percent / paraformaldehyde, boron trifluoride etherate / H2O; acetone / 120 h / Ambient temperature View Scheme