1.1: DCC; DMAP / CH2Cl2 / 72 h / 20 °C 2.1: 87 percent / aq. AcOH / tetrahydrofuran / 15 h / 70 - 110 °C 3.1: 75 percent / DCC; (+)-camphorsulfonic acid; DMAP / CH2Cl2 / 48 h / 20 °C 4.1: 79 percent / aq. AcOH / tetrahydrofuran / 48 h / 80 °C 5.1: 79 percent / DCC; DMAP; (+)-comphorsulfonic acid / CH2Cl2 / 48 h / 20 °C 6.1: 96 percent / aq. AcOH / tetrahydrofuran / 3 h / 80 °C 7.1: Zn dust; aq. AcOH-AcONa buffer / tetrahydrofuran / 2.5 h / 20 °C 8.1: 2,4,6-trichlorbenzoyl chloride; 4A mol sieves; Et3N / 3 h / 20 °C 8.2: DMAP / toluene / 24 h / 100 °C 9.1: 75 percent / AlCl3; m-xylene / CH2Cl2 / 2 h / 0 °C View Scheme