1: cerium chloride (CeCl3*7H2O) / methanol 2: 44 percent / t-butyl lithium / tetrahydrofuran 3: 52 percent / BF3*OEt2 / CH2Cl2 / -55 °C 4: 1.) irradiation at 300 nm, benzene 2.) 1O2, CH3OH View Scheme

hydrogenchloride; n-butyllithium; chloro-trimethyl-silane; diethyl ether in tetrahydrofuran; hexane

1: cerium chloride (CeCl3*7H2O) / methanol 2: 44 percent / t-butyl lithium / tetrahydrofuran View Scheme