1: (i) SOCl2, Py, THF, (ii) /BRN= 102415/, Et2O, benzene 2: benzene; diethyl ether 3: (i) aq. MeOH, (ii) aq. NaOH 4: H2 / PdO / ethanol 5: Ag2O, MgSO4 / benzene View Scheme