1: 95 percent / DDQ / CH2Cl2; H2O / 0.17 h / Ambient temperature 2: 70 percent / TFA, molecular sieves / CH2Cl2 View Scheme

Multi-step reaction with 6 steps 1: DMSO, (COCl)2 / CH2Cl2 2: TsOH / benzene3: H2 / Pd-C / ethyl acetate4: CrO3, H2SO4 / acetone5: 2N-HCl / tetrahydrofuran / Ambient temperature6: 23 percent / (C6H11)2NMgBr / tetrahydrofuran / -55 °C