1.1: 89 percent / MeLi / tetrahydrofuran / 0.33 h / -78 °C 2.1: 82 percent / p-TsOH / CH2Cl2 / 2 h / 20 °C 3.1: 90 percent / Bu4NF / tetrahydrofuran / 12 h / 20 °C 4.1: NaH; 15-crown-5 / tetrahydrofuran / 14 h / Heating 4.2: 93 percent / Bu4NF / tetrahydrofuran 5.1: 59 percent / (PhO)2P(O)N3; DIAD; PPh3 / toluene / 12 h / 20 °C 6.1: 82 percent / p-TsOH / methanol / 12 h / 20 °C 7.1: Zn; NH4Cl / methanol / 12 h / 20 °C View Scheme

1.1: 89 percent / MeLi / tetrahydrofuran / 0.33 h / -78 °C 2.1: 82 percent / p-TsOH / CH2Cl2 / 2 h / 20 °C 3.1: 90 percent / Bu4NF / tetrahydrofuran / 12 h / 20 °C 4.1: NaH; 15-crown-5 / tetrahydrofuran / 14 h / Heating 4.2: 93 percent / Bu4NF / tetrahydrofuran 5.1: 59 percent / (PhO)2P(O)N3; DIAD; PPh3 / toluene / 12 h / 20 °C 6.1: 82 percent / p-TsOH / methanol / 12 h / 20 °C View Scheme

1.1: 89 percent / MeLi / tetrahydrofuran / 0.33 h / -78 °C 2.1: 82 percent / p-TsOH / CH2Cl2 / 2 h / 20 °C 3.1: 90 percent / Bu4NF / tetrahydrofuran / 12 h / 20 °C 4.1: NaH; 15-crown-5 / tetrahydrofuran / 14 h / Heating 4.2: 93 percent / Bu4NF / tetrahydrofuran 5.1: 59 percent / (PhO)2P(O)N3; DIAD; PPh3 / toluene / 12 h / 20 °C 6.1: 82 percent / p-TsOH / methanol / 12 h / 20 °C 7.1: Zn; NH4Cl / methanol / 12 h / 20 °C View Scheme

1.1: 89 percent / MeLi / tetrahydrofuran / 0.33 h / -78 °C 2.1: 82 percent / p-TsOH / CH2Cl2 / 2 h / 20 °C 3.1: 90 percent / Bu4NF / tetrahydrofuran / 12 h / 20 °C 4.1: NaH; 15-crown-5 / tetrahydrofuran / 14 h / Heating 4.2: 93 percent / Bu4NF / tetrahydrofuran View Scheme

1.1: 89 percent / MeLi / tetrahydrofuran / 0.33 h / -78 °C 2.1: 82 percent / p-TsOH / CH2Cl2 / 2 h / 20 °C 3.1: 90 percent / Bu4NF / tetrahydrofuran / 12 h / 20 °C 4.1: NaH; 15-crown-5 / tetrahydrofuran / 14 h / Heating 4.2: 93 percent / Bu4NF / tetrahydrofuran 5.1: 59 percent / (PhO)2P(O)N3; DIAD; PPh3 / toluene / 12 h / 20 °C 6.1: 82 percent / p-TsOH / methanol / 12 h / 20 °C 7.1: Zn; NH4Cl / methanol / 12 h / 20 °C View Scheme