1.1: 86 percent / K2CO3 / CH2Cl2 / 3 h / 0 °C 2.1: LDA / tetrahydrofuran / 0.25 h / -78 °C 2.2: 71 percent / tetrahydrofuran / 0.17 h 3.1: 95 percent / borontrifluoride etherate / CH2Cl2 / 4 h / 20 °C 4.1: p-TsOH / CH2Cl2 / 3 h / 20 °C 5.1: DMAP / CH2Cl2 / 12 h / 20 °C 6.1: 85 percent / p-TsOH / methanol / 12 h / 20 °C 7.1: 88 percent / LDA; HMPA / tetrahydrofuran / 4 h / -78 °C 8.1: 75 percent / trifluoroacetic acid / CH2Cl2 / 3 h / 20 °C 9.1: aq. NaOH / 72 h / 20 °C 10.1: 16 mg / triethylamine; bis(2-oxo-3-oxazolidinyl)phosphonic chloride / CH2Cl2 / 3 h / 20 °C View Scheme

1.1: LDA / tetrahydrofuran / 0.25 h / -78 °C 1.2: 71 percent / tetrahydrofuran / 0.17 h 2.1: 95 percent / borontrifluoride etherate / CH2Cl2 / 4 h / 20 °C 3.1: p-TsOH / CH2Cl2 / 3 h / 20 °C 4.1: DMAP / CH2Cl2 / 12 h / 20 °C 5.1: 85 percent / p-TsOH / methanol / 12 h / 20 °C 6.1: 88 percent / LDA; HMPA / tetrahydrofuran / 4 h / -78 °C 7.1: 75 percent / trifluoroacetic acid / CH2Cl2 / 3 h / 20 °C 8.1: aq. NaOH / 72 h / 20 °C 9.1: 16 mg / triethylamine; bis(2-oxo-3-oxazolidinyl)phosphonic chloride / CH2Cl2 / 3 h / 20 °C View Scheme

1.1: 2.13 g / methanol; toluene / 1 h / 0 °C 2.1: 86 percent / K2CO3 / CH2Cl2 / 3 h / 0 °C 3.1: LDA / tetrahydrofuran / 0.25 h / -78 °C 3.2: 71 percent / tetrahydrofuran / 0.17 h 4.1: 95 percent / borontrifluoride etherate / CH2Cl2 / 4 h / 20 °C 5.1: p-TsOH / CH2Cl2 / 3 h / 20 °C 6.1: DMAP / CH2Cl2 / 12 h / 20 °C 7.1: 85 percent / p-TsOH / methanol / 12 h / 20 °C 8.1: 88 percent / LDA; HMPA / tetrahydrofuran / 4 h / -78 °C 9.1: 75 percent / trifluoroacetic acid / CH2Cl2 / 3 h / 20 °C 10.1: aq. NaOH / 72 h / 20 °C 11.1: 16 mg / triethylamine; bis(2-oxo-3-oxazolidinyl)phosphonic chloride / CH2Cl2 / 3 h / 20 °C View Scheme

1.1: 91 percent / Dowex(R) 50Wx8-100 resin / aq. methanol / 16 h / 20 °C 2.1: ruthenium(IV) oxide hydrate; sodium periodate / CCl4; acetonitrile; H2O / 3 h / 20 °C 3.1: 2.13 g / methanol; toluene / 1 h / 0 °C 4.1: 86 percent / K2CO3 / CH2Cl2 / 3 h / 0 °C 5.1: LDA / tetrahydrofuran / 0.25 h / -78 °C 5.2: 71 percent / tetrahydrofuran / 0.17 h 6.1: 95 percent / borontrifluoride etherate / CH2Cl2 / 4 h / 20 °C 7.1: p-TsOH / CH2Cl2 / 3 h / 20 °C 8.1: DMAP / CH2Cl2 / 12 h / 20 °C 9.1: 85 percent / p-TsOH / methanol / 12 h / 20 °C 10.1: 88 percent / LDA; HMPA / tetrahydrofuran / 4 h / -78 °C 11.1: 75 percent / trifluoroacetic acid / CH2Cl2 / 3 h / 20 °C 12.1: aq. NaOH / 72 h / 20 °C 13.1: 16 mg / triethylamine; bis(2-oxo-3-oxazolidinyl)phosphonic chloride / CH2Cl2 / 3 h / 20 °C View Scheme

1.1: 90 percent / dimethylformamide / 6 h / 20 °C 2.1: 85 percent / p-N-acetylbenzosulfonylazide; DBU / acetonitrile / 1 h / 0 °C 3.1: 85 percent / Rh2(OAc)4 / CH2Cl2 / 12 h / Heating 4.1: 90 percent / sodium amalgam; disodium hydrogen phosphate / methanol / 2 h / 0 °C 5.1: 91 percent / Dowex(R) 50Wx8-100 resin / aq. methanol / 16 h / 20 °C 6.1: ruthenium(IV) oxide hydrate; sodium periodate / CCl4; acetonitrile; H2O / 3 h / 20 °C 7.1: 2.13 g / methanol; toluene / 1 h / 0 °C 8.1: 86 percent / K2CO3 / CH2Cl2 / 3 h / 0 °C 9.1: LDA / tetrahydrofuran / 0.25 h / -78 °C 9.2: 71 percent / tetrahydrofuran / 0.17 h 10.1: 95 percent / borontrifluoride etherate / CH2Cl2 / 4 h / 20 °C 11.1: p-TsOH / CH2Cl2 / 3 h / 20 °C 12.1: DMAP / CH2Cl2 / 12 h / 20 °C 13.1: 85 percent / p-TsOH / methanol / 12 h / 20 °C 14.1: 88 percent / LDA; HMPA / tetrahydrofuran / 4 h / -78 °C 15.1: 75 percent / trifluoroacetic acid / CH2Cl2 / 3 h / 20 °C 16.1: aq. NaOH / 72 h / 20 °C 17.1: 16 mg / triethylamine; bis(2-oxo-3-oxazolidinyl)phosphonic chloride / CH2Cl2 / 3 h / 20 °C View Scheme

1: p-TsOH / CH2Cl2 / 3 h / 20 °C 2: DMAP / CH2Cl2 / 12 h / 20 °C 3: 85 percent / p-TsOH / methanol / 12 h / 20 °C 4: 88 percent / LDA; HMPA / tetrahydrofuran / 4 h / -78 °C 5: 75 percent / trifluoroacetic acid / CH2Cl2 / 3 h / 20 °C 6: aq. NaOH / 72 h / 20 °C 7: 16 mg / triethylamine; bis(2-oxo-3-oxazolidinyl)phosphonic chloride / CH2Cl2 / 3 h / 20 °C View Scheme

1: 95 percent / borontrifluoride etherate / CH2Cl2 / 4 h / 20 °C 2: p-TsOH / CH2Cl2 / 3 h / 20 °C 3: DMAP / CH2Cl2 / 12 h / 20 °C 4: 85 percent / p-TsOH / methanol / 12 h / 20 °C 5: 88 percent / LDA; HMPA / tetrahydrofuran / 4 h / -78 °C 6: 75 percent / trifluoroacetic acid / CH2Cl2 / 3 h / 20 °C 7: aq. NaOH / 72 h / 20 °C 8: 16 mg / triethylamine; bis(2-oxo-3-oxazolidinyl)phosphonic chloride / CH2Cl2 / 3 h / 20 °C View Scheme

1.1: 90 percent / sodium amalgam; disodium hydrogen phosphate / methanol / 2 h / 0 °C 2.1: 91 percent / Dowex(R) 50Wx8-100 resin / aq. methanol / 16 h / 20 °C 3.1: ruthenium(IV) oxide hydrate; sodium periodate / CCl4; acetonitrile; H2O / 3 h / 20 °C 4.1: 2.13 g / methanol; toluene / 1 h / 0 °C 5.1: 86 percent / K2CO3 / CH2Cl2 / 3 h / 0 °C 6.1: LDA / tetrahydrofuran / 0.25 h / -78 °C 6.2: 71 percent / tetrahydrofuran / 0.17 h 7.1: 95 percent / borontrifluoride etherate / CH2Cl2 / 4 h / 20 °C 8.1: p-TsOH / CH2Cl2 / 3 h / 20 °C 9.1: DMAP / CH2Cl2 / 12 h / 20 °C 10.1: 85 percent / p-TsOH / methanol / 12 h / 20 °C 11.1: 88 percent / LDA; HMPA / tetrahydrofuran / 4 h / -78 °C 12.1: 75 percent / trifluoroacetic acid / CH2Cl2 / 3 h / 20 °C 13.1: aq. NaOH / 72 h / 20 °C 14.1: 16 mg / triethylamine; bis(2-oxo-3-oxazolidinyl)phosphonic chloride / CH2Cl2 / 3 h / 20 °C View Scheme

1.1: 85 percent / p-N-acetylbenzosulfonylazide; DBU / acetonitrile / 1 h / 0 °C 2.1: 85 percent / Rh2(OAc)4 / CH2Cl2 / 12 h / Heating 3.1: 90 percent / sodium amalgam; disodium hydrogen phosphate / methanol / 2 h / 0 °C 4.1: 91 percent / Dowex(R) 50Wx8-100 resin / aq. methanol / 16 h / 20 °C 5.1: ruthenium(IV) oxide hydrate; sodium periodate / CCl4; acetonitrile; H2O / 3 h / 20 °C 6.1: 2.13 g / methanol; toluene / 1 h / 0 °C 7.1: 86 percent / K2CO3 / CH2Cl2 / 3 h / 0 °C 8.1: LDA / tetrahydrofuran / 0.25 h / -78 °C 8.2: 71 percent / tetrahydrofuran / 0.17 h 9.1: 95 percent / borontrifluoride etherate / CH2Cl2 / 4 h / 20 °C 10.1: p-TsOH / CH2Cl2 / 3 h / 20 °C 11.1: DMAP / CH2Cl2 / 12 h / 20 °C 12.1: 85 percent / p-TsOH / methanol / 12 h / 20 °C 13.1: 88 percent / LDA; HMPA / tetrahydrofuran / 4 h / -78 °C 14.1: 75 percent / trifluoroacetic acid / CH2Cl2 / 3 h / 20 °C 15.1: aq. NaOH / 72 h / 20 °C 16.1: 16 mg / triethylamine; bis(2-oxo-3-oxazolidinyl)phosphonic chloride / CH2Cl2 / 3 h / 20 °C View Scheme

1.1: 85 percent / Rh2(OAc)4 / CH2Cl2 / 12 h / Heating 2.1: 90 percent / sodium amalgam; disodium hydrogen phosphate / methanol / 2 h / 0 °C 3.1: 91 percent / Dowex(R) 50Wx8-100 resin / aq. methanol / 16 h / 20 °C 4.1: ruthenium(IV) oxide hydrate; sodium periodate / CCl4; acetonitrile; H2O / 3 h / 20 °C 5.1: 2.13 g / methanol; toluene / 1 h / 0 °C 6.1: 86 percent / K2CO3 / CH2Cl2 / 3 h / 0 °C 7.1: LDA / tetrahydrofuran / 0.25 h / -78 °C 7.2: 71 percent / tetrahydrofuran / 0.17 h 8.1: 95 percent / borontrifluoride etherate / CH2Cl2 / 4 h / 20 °C 9.1: p-TsOH / CH2Cl2 / 3 h / 20 °C 10.1: DMAP / CH2Cl2 / 12 h / 20 °C 11.1: 85 percent / p-TsOH / methanol / 12 h / 20 °C 12.1: 88 percent / LDA; HMPA / tetrahydrofuran / 4 h / -78 °C 13.1: 75 percent / trifluoroacetic acid / CH2Cl2 / 3 h / 20 °C 14.1: aq. NaOH / 72 h / 20 °C 15.1: 16 mg / triethylamine; bis(2-oxo-3-oxazolidinyl)phosphonic chloride / CH2Cl2 / 3 h / 20 °C View Scheme