1: 1.) Et3N, 2.) 36percent HCl / 1.) CHCl3, R.T., overnight, 2.) H2O, reflux, 5 h 2: pyridine / 4 h / 0 °C View Scheme

pyridine T=0°C; 4 h; Yield given;

in pyridine T=0°C; 4 h; Yield given. Title compound not separated from byproducts;

toluene-4-sulfonic acid

4 h; Irradiation; Product distribution;

1: 74.8 percent / diethyl ether / 40 h / -60 - -50 °C / Irradiation 2: 86.6 percent / 4 percent KOH / dioxane; H2O / 1.5 h / Ambient temperature 3: 93.7 percent / L-Selectride / tetrahydrofuran / 3 h / -78 °C 4: 92.4 percent / pyridine / Ambient temperature 5: 81.9 percent / potassium t-butoxide / 2-methyl-propan-2-ol / 1 h / 40 °C 6: H2 / PtO2 / diethyl ether / 760 Torr / Ambient temperature View Scheme