1.1: sodium t-butanolate / tert-butyl methyl ether / 2 h / 5 - 20 °C 2.1: (S)-pyrophosphoric acid / water / 2 h / 0 - 60 °C 3.1: 1,8-diazabicyclo[5.4.0]undec-7-ene / 20 - 35 °C 4.1: hydrogen / Ni-Raney / tetrahydrofuran / 48 h / 20 °C / 2585.81 - 3102.97 Torr 5.1: ethyl acetate / 96 h / 25 °C 6.1: boron trifluoride diethyl etherate; triethylsilane / 24 h / 105 °C 7.1: sodium hydroxide / dichloromethane; water / pH > 10 7.2: 2 h / 60 °C View Scheme

1.1: sodium t-butanolate / tert-butyl methyl ether / 2 h / 5 - 20 °C 2.1: (S)-pyrophosphoric acid / water / 2 h / 0 - 60 °C 3.1: 1,8-diazabicyclo[5.4.0]undec-7-ene / 20 - 35 °C 4.1: hydrogen / Ni-Raney / tetrahydrofuran / 48 h / 20 °C / 2585.81 - 3102.97 Torr 5.1: ethyl acetate / 96 h / 25 °C 6.1: lithium aluminium tetrahydride; AlCl3, aluminium chloride / tetrahydrofuran / 0 - 20 °C 6.2: 0.33 h / 2 °C View Scheme

Multi-step reaction with 3 steps 1.1: potassium carbonate / copper / 10 h / 130 °C2.1: morpholine; sulfur / 12 h / 110 °C2.2: 8 h / Reflux3.1: sulfuric acid / 2 h / 50 °C