1: 95 percent / NaOMe / 4 h / Heating 2: 85 percent / HCl / H2O / 3 h / Heating 3: 1) HMDS, Me3SiCl, 2) stannic chloride / 1) reflux, 2) CH3CN, room temperature, 10 h View Scheme

1: 95 percent / NaOMe / 4 h / Heating 2: 85 percent / HCl / H2O / 3 h / Heating View Scheme