1: 63 percent / LiCl / hexamethylphosphoric acid triamide / 5 h / Ambient temperature 2: 82 percent / tetra-n-butylammonium fluoride / tetrahydrofuran / 0.17 h / Ambient temperature View Scheme

1: 82 percent / hexamethylphosphoric acid triamide / 6 h / Ambient temperature 2: tetra-n-butylammonium fluoride / tetrahydrofuran / 0.17 h / Ambient temperature 3: NH3 View Scheme

1: 92 percent / LiN3 / hexamethylphosphoric acid triamide / 4 h / Ambient temperature 2: 87 percent / tetra-n-butylammonium fluoride / tetrahydrofuran / 0.17 h / Ambient temperature View Scheme

1: 82 percent / hexamethylphosphoric acid triamide / 6 h / Ambient temperature 2: 89 percent / triethylamine / methanol / 48 h / Ambient temperature 3: 77 percent / triethylamine, DMAP / CH2Cl2 / 0.5 h / Ambient temperature 4: 90 percent / LiCl / hexamethylphosphoric acid triamide / 1 h / Ambient temperature 5: 84 percent / tetra-n-butylammonium fluoride / tetrahydrofuran / 0.17 h / Ambient temperature View Scheme