trifluoroacetic acid in dichloromethane desilylation;

in dichloromethane equimolar amts., stirring overnight; evapn. (reduced pressure), crystn. (water);

1.1: 92 percent / sodium hydride in oil / tetrahydrofuran / 14 h / 20 °C 2.1: n-butyl lithium / tetrahydrofuran; hexane / 0.25 h / -78 °C 2.2: 77 percent / tri-isopropyl borate / tetrahydrofuran / 4 h / -78 - -20 °C 3.1: 88 percent / trifluoroacetic acid / CH2Cl2 View Scheme

1.1: n-butyl lithium / tetrahydrofuran; hexane / 0.25 h / -78 °C 1.2: 77 percent / tri-isopropyl borate / tetrahydrofuran / 4 h / -78 - -20 °C 2.1: 88 percent / trifluoroacetic acid / CH2Cl2 View Scheme

potassium carbonate in acetonitrile Methylation;