Multi-step reaction with 14 steps 1: DMAP2: K2CO3 / methanol3: MnO2 / (COCl)2, DMSO and Et3N4: 1.) TMEDA, n-BuLi 2.) ClTi(O-iPr)3 / 1.) ether, hexane, -78 deg C, 1 h 2.) ether, hexane, -78 deg C, 2 h then -10 deg C, 1.5 h5: LiAlH4 / tetrahydrofuran / 0.5 h / 0 °C / Heating6: PPTS / CH2Cl2 / 0.08 h / Ambient temperature7: 1.) B2H6, 2-methyl-2-butene 3.) 3M NaOH, 30percent aq. H2O2 / 1.) THF, -10 deg C, 2 h 2.) THF, 0 deg C, 30 min; 3.) THF, RT, 30 min.8: 90 percent / triphenylphosphine, imidazole, I2 / tetrahydrofuran; acetonitrile / 0.5 h / -10 °C9: 1.) NaH / 1.) DMSO, RT, 30 min; 2.) DMSO, overnight10: MeOH / PPTS / 0.08 h / Heating11: 1.) DMSO, (COCl)2 2.) Et3N / 1.) CH2Cl2, -78 deg C, 30 min; 2.) CH2Cl2, -78 to 0 deg C12: 35 percent / K2CO3, 18-crown-6 / toluene / 80 °C13: H2O / PPTS / tetrahydrofuran / 1.5 h / Heating14: PCC, sodium acetate / CH2Cl2 / 2.5 h  

Multi-step reaction with 15 steps 1: DMAP2: K2CO3 / methanol3: MnO2 / (COCl)2, DMSO and Et3N4: 1.) TMEDA, n-BuLi 2.) ClTi(O-iPr)3 / 1.) ether, hexane, -78 deg C, 1 h 2.) ether, hexane, -78 deg C, 2 h then -10 deg C, 1.5 h5: LiAlH4 / tetrahydrofuran / 0.5 h / 0 °C / Heating6: PPTS / CH2Cl2 / 0.08 h / Ambient temperature7: 1.) B2H6, 2-methyl-2-butene 3.) 3M NaOH, 30percent aq. H2O2 / 1.) THF, -10 deg C, 2 h 2.) THF, 0 deg C, 30 min; 3.) THF, RT, 30 min.8: 90 percent / triphenylphosphine, imidazole, I2 / tetrahydrofuran; acetonitrile / 0.5 h / -10 °C9: 1.) NaH / 1.) DMSO, RT, 30 min; 2.) DMSO, overnight10: MeOH / PPTS / 0.08 h / Heating11: 1.) DMSO, (COCl)2 2.) Et3N / 1.) CH2Cl2, -78 deg C, 30 min; 2.) CH2Cl2, -78 to 0 deg C12: 35 percent / K2CO3, 18-crown-6 / toluene / 80 °C13: H2O / PPTS / tetrahydrofuran / 1.5 h / Heating14: PCC, sodium acetate / CH2Cl2 / 2.5 h15: 1.) LDA, 1,10-phenanthroline / 1.) THF, -78 deg C, 15 min; 2.) THF, -20 deg C, 5 min.  

Multi-step reaction with 9 steps 1: DMAP2: K2CO3 / methanol3: MnO2 / (COCl)2, DMSO and Et3N4: 1.) TMEDA, n-BuLi 2.) ClTi(O-iPr)3 / 1.) ether, hexane, -78 deg C, 1 h 2.) ether, hexane, -78 deg C, 2 h then -10 deg C, 1.5 h5: LiAlH4 / tetrahydrofuran / 0.5 h / 0 °C / Heating6: PPTS / CH2Cl2 / 0.08 h / Ambient temperature7: 1.) B2H6, 2-methyl-2-butene 3.) 3M NaOH, 30percent aq. H2O2 / 1.) THF, -10 deg C, 2 h 2.) THF, 0 deg C, 30 min; 3.) THF, RT, 30 min.8: 90 percent / triphenylphosphine, imidazole, I2 / tetrahydrofuran; acetonitrile / 0.5 h / -10 °C9: 1.) NaH / 1.) DMSO 2.) DMSO  

Multi-step reaction with 13 steps 1: DMAP2: K2CO3 / methanol3: MnO2 / (COCl)2, DMSO and Et3N4: 1.) TMEDA, n-BuLi 2.) ClTi(O-iPr)3 / 1.) ether, hexane, -78 deg C, 1 h 2.) ether, hexane, -78 deg C, 2 h then -10 deg C, 1.5 h5: LiAlH4 / tetrahydrofuran / 0.5 h / 0 °C / Heating6: PPTS / CH2Cl2 / 0.08 h / Ambient temperature7: 1.) B2H6, 2-methyl-2-butene 3.) 3M NaOH, 30percent aq. H2O2 / 1.) THF, -10 deg C, 2 h 2.) THF, 0 deg C, 30 min; 3.) THF, RT, 30 min.8: 90 percent / triphenylphosphine, imidazole, I2 / tetrahydrofuran; acetonitrile / 0.5 h / -10 °C9: 1.) NaH / 1.) DMSO, RT, 30 min; 2.) DMSO, overnight10: MeOH / PPTS / 0.08 h / Heating11: 1.) DMSO, (COCl)2 2.) Et3N / 1.) CH2Cl2, -78 deg C, 30 min; 2.) CH2Cl2, -78 to 0 deg C12: 35 percent / K2CO3, 18-crown-6 / toluene / 80 °C13: H2O / PPTS / tetrahydrofuran / 1.5 h / Heating  

Multi-step reaction with 10 steps 1: DMAP2: K2CO3 / methanol3: MnO2 / (COCl)2, DMSO and Et3N4: 1.) TMEDA, n-BuLi 2.) ClTi(O-iPr)3 / 1.) ether, hexane, -78 deg C, 1 h 2.) ether, hexane, -78 deg C, 2 h then -10 deg C, 1.5 h5: LiAlH4 / tetrahydrofuran / 0.5 h / 0 °C / Heating6: PPTS / CH2Cl2 / 0.08 h / Ambient temperature7: 1.) B2H6, 2-methyl-2-butene 3.) 3M NaOH, 30percent aq. H2O2 / 1.) THF, -10 deg C, 2 h 2.) THF, 0 deg C, 30 min; 3.) THF, RT, 30 min.8: 90 percent / triphenylphosphine, imidazole, I2 / tetrahydrofuran; acetonitrile / 0.5 h / -10 °C9: 1.) NaH / 1.) DMSO 2.) DMSO10: MeOH, PPTS