1: 84 percent / 2,4,6-trichlorobenzoyl chloride; Et3N; DMAP / tetrahydrofuran; toluene / 12 h / 20 °C 2: 81 percent / DBN / benzene / 8 h / 20 °C 3: 82 percent / 2,4,6-trichlorobenzoyl chloride; Et3N; DMAP / tetrahydrofuran; toluene / 12 h / 20 °C 4: 77 percent / TMSCl; NaI / acetonitrile / 6 h / -20 °C 5: 79 percent / DBN / benzene / 8 h / 20 °C 6: 67 percent / 2,4,6-trichlorobenzoyl chloride; Et3N; DMAP / tetrahydrofuran; toluene / 24 h / 90 °C 7: 90 percent / DDQ / CH2Cl2; H2O / 20 °C View Scheme