Celite; silver carbonate in toluene T=85 - 95°C; 1 h;

hydrogen fluoride in acetonitrile T=25°C; 1.4 h;

phosphoric acid in water; toluene T=20 - 55°C; pH=3.5; 19 h; Product distribution / selectivity;

1: 50 percent / (Ph3P)3RhCl / toluene; acetonitrile / 2.5 h / Heating 2: 1.) LDA / 1.)Et2O, -78 deg C, 45 min; 2.) -78 deg C, 10 min 3: 85 percent / i-Pr2NH / DMAP / diethyl ether / 24 h / Ambient temperature 4: 1.) O3; 2.) Ph3P / 1.) CH2Cl2, -78 deg C; 2.) -78 deg C -> r.t., 3 h 5: 86 percent / C8K, TiCl3 / 1,2-dimethoxy-ethane / r.t., 5 h; reflux, 4 h 6: 1.) Bu4NF ; 2.) t-BuPh2SiCl, Et3N / 2.) DMAP / 1.) THF, r.t., 22 h; 2.) CH2Cl2, r.t., 24 h 7: 97 percent / Et3N / DMAP / CH2Cl2 / 88 h / Ambient temperature 8: 95 percent / Bu4NF / tetrahydrofuran / 3 h / Ambient temperature 9: 1.) (COCl)2; 2.) Et3N / 1.) DMSO, CH2Cl2, -78 deg C, 20 min; 2.) -78 deg C, 10 min, -78 deg C -> r.t., 20 min 10: 97 percent / 1.3N HCl / tetrahydrofuran / 4 h / Ambient temperature 11: 77 percent / Ag2CO3/Celite, PhMe / toluene / 1 h / 90 °C View Scheme

1: 97 percent / Et3N / DMAP / CH2Cl2 / 88 h / Ambient temperature 2: 95 percent / Bu4NF / tetrahydrofuran / 3 h / Ambient temperature 3: 1.) (COCl)2; 2.) Et3N / 1.) DMSO, CH2Cl2, -78 deg C, 20 min; 2.) -78 deg C, 10 min, -78 deg C -> r.t., 20 min 4: 97 percent / 1.3N HCl / tetrahydrofuran / 4 h / Ambient temperature 5: 77 percent / Ag2CO3/Celite, PhMe / toluene / 1 h / 90 °C View Scheme

1: 85 percent / i-Pr2NH / DMAP / diethyl ether / 24 h / Ambient temperature 2: 1.) O3; 2.) Ph3P / 1.) CH2Cl2, -78 deg C; 2.) -78 deg C -> r.t., 3 h 3: 86 percent / C8K, TiCl3 / 1,2-dimethoxy-ethane / r.t., 5 h; reflux, 4 h 4: 1.) Bu4NF ; 2.) t-BuPh2SiCl, Et3N / 2.) DMAP / 1.) THF, r.t., 22 h; 2.) CH2Cl2, r.t., 24 h 5: 97 percent / Et3N / DMAP / CH2Cl2 / 88 h / Ambient temperature 6: 95 percent / Bu4NF / tetrahydrofuran / 3 h / Ambient temperature 7: 1.) (COCl)2; 2.) Et3N / 1.) DMSO, CH2Cl2, -78 deg C, 20 min; 2.) -78 deg C, 10 min, -78 deg C -> r.t., 20 min 8: 97 percent / 1.3N HCl / tetrahydrofuran / 4 h / Ambient temperature 9: 77 percent / Ag2CO3/Celite, PhMe / toluene / 1 h / 90 °C View Scheme

1: 1.) Bu4NF ; 2.) t-BuPh2SiCl, Et3N / 2.) DMAP / 1.) THF, r.t., 22 h; 2.) CH2Cl2, r.t., 24 h 2: 97 percent / Et3N / DMAP / CH2Cl2 / 88 h / Ambient temperature 3: 95 percent / Bu4NF / tetrahydrofuran / 3 h / Ambient temperature 4: 1.) (COCl)2; 2.) Et3N / 1.) DMSO, CH2Cl2, -78 deg C, 20 min; 2.) -78 deg C, 10 min, -78 deg C -> r.t., 20 min 5: 97 percent / 1.3N HCl / tetrahydrofuran / 4 h / Ambient temperature 6: 77 percent / Ag2CO3/Celite, PhMe / toluene / 1 h / 90 °C View Scheme

1: 1.) O3; 2.) Ph3P / 1.) CH2Cl2, -78 deg C; 2.) -78 deg C -> r.t., 3 h 2: 86 percent / C8K, TiCl3 / 1,2-dimethoxy-ethane / r.t., 5 h; reflux, 4 h 3: 1.) Bu4NF ; 2.) t-BuPh2SiCl, Et3N / 2.) DMAP / 1.) THF, r.t., 22 h; 2.) CH2Cl2, r.t., 24 h 4: 97 percent / Et3N / DMAP / CH2Cl2 / 88 h / Ambient temperature 5: 95 percent / Bu4NF / tetrahydrofuran / 3 h / Ambient temperature 6: 1.) (COCl)2; 2.) Et3N / 1.) DMSO, CH2Cl2, -78 deg C, 20 min; 2.) -78 deg C, 10 min, -78 deg C -> r.t., 20 min 7: 97 percent / 1.3N HCl / tetrahydrofuran / 4 h / Ambient temperature 8: 77 percent / Ag2CO3/Celite, PhMe / toluene / 1 h / 90 °C View Scheme

1: 86 percent / C8K, TiCl3 / 1,2-dimethoxy-ethane / r.t., 5 h; reflux, 4 h 2: 1.) Bu4NF ; 2.) t-BuPh2SiCl, Et3N / 2.) DMAP / 1.) THF, r.t., 22 h; 2.) CH2Cl2, r.t., 24 h 3: 97 percent / Et3N / DMAP / CH2Cl2 / 88 h / Ambient temperature 4: 95 percent / Bu4NF / tetrahydrofuran / 3 h / Ambient temperature 5: 1.) (COCl)2; 2.) Et3N / 1.) DMSO, CH2Cl2, -78 deg C, 20 min; 2.) -78 deg C, 10 min, -78 deg C -> r.t., 20 min 6: 97 percent / 1.3N HCl / tetrahydrofuran / 4 h / Ambient temperature 7: 77 percent / Ag2CO3/Celite, PhMe / toluene / 1 h / 90 °C View Scheme

1: 1.) LDA / 1.)Et2O, -78 deg C, 45 min; 2.) -78 deg C, 10 min 2: 85 percent / i-Pr2NH / DMAP / diethyl ether / 24 h / Ambient temperature 3: 1.) O3; 2.) Ph3P / 1.) CH2Cl2, -78 deg C; 2.) -78 deg C -> r.t., 3 h 4: 86 percent / C8K, TiCl3 / 1,2-dimethoxy-ethane / r.t., 5 h; reflux, 4 h 5: 1.) Bu4NF ; 2.) t-BuPh2SiCl, Et3N / 2.) DMAP / 1.) THF, r.t., 22 h; 2.) CH2Cl2, r.t., 24 h 6: 97 percent / Et3N / DMAP / CH2Cl2 / 88 h / Ambient temperature 7: 95 percent / Bu4NF / tetrahydrofuran / 3 h / Ambient temperature 8: 1.) (COCl)2; 2.) Et3N / 1.) DMSO, CH2Cl2, -78 deg C, 20 min; 2.) -78 deg C, 10 min, -78 deg C -> r.t., 20 min 9: 97 percent / 1.3N HCl / tetrahydrofuran / 4 h / Ambient temperature 10: 77 percent / Ag2CO3/Celite, PhMe / toluene / 1 h / 90 °C View Scheme