methanol; potassium carbonate

in dimethyl sulfoxide 2 h;

1.1: diisopropylamine; nBuLi; 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone / tetrahydrofuran; hexane / 0.5 h / 0 °C 1.2: 63 percent / tetrahydrofuran; hexane / 17 h / -78 - 20 °C 2.1: 73 percent / OsO4; NaIO4 / H2O; 2-methyl-propan-2-ol / 1 h 3.1: 79 percent / K2CO3 / methanol / 22 h View Scheme

1: 73 percent / OsO4; NaIO4 / H2O; 2-methyl-propan-2-ol / 1 h 2: 79 percent / K2CO3 / methanol / 22 h View Scheme