2-propan-2-ylsulfanylpropane

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of 9.63 g (29.81 mmol) of 2-(4,5-dibromo-2-furanyl)-4,4-dimethyloxazoline in dry tetrahydrofuran (30 mL) is added dropwise to a -78° C. solution of freshly generated lithium diisopropylamide (33.89 mmol, 1.14 equiv) in tetrahydrofuran (80 mL) under an argon atmosphere. The resulting solution is stirred at -78° C. for 10 min and a solution of 5.49 g (46.49 mmol, 1.56 equiv) of isopropyl sulfide in tetrahydrofuran (20 mL) is added dropwise to the reaction. The reaction is stirred for 3.75 hr at -78° to -10° C. and poured onto 5% aqueous HCl (350 mL). The resulting aqueous solution is extracted with diethyl ether (4X). The combined organic extracts are washed with aqueous saturated NaCl, dried (Na2SO4), and concentrated in vacuo. Flash chromatography (SiO2, 7×25 cm, 10% CH2Cl2 /10% ethyl acetate/hexane) affords 7.67 g (11.84 g theo.; 65%) of the desired product as a yellow solid. Recrystallization from hexane affords an analytical sample; mp 71°-72° C. The reaction is stirred for 3.75 hr at -78° to -10° C. The resulting aqueous solution is extracted with diethyl ether (4X) The combined organic extracts are washed with aqueous saturated NaCl dried (Na2SO4) concentrated in vacuo

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of 25.01 g (136.0 mmol) of 5-trimethylsilyl-2-furancarboxylic acid (Carpenter, A. J. and Chadwick, D. J., Tetrahedron Lett., 26, 1777 (1985)) in 50 mL of dry tetrahydrofuran is added over 10 minutes to a -76° C. solution of freshly generated lithium diisopropylamide (328.0 mmol, 2.41 equiv) in dry tetrahydrofuran (175 mL) under nitrogen atmosphere and the resulting mixture is stirred at -76° to 65° C. for 1.5 hours. The reaction is recooled to -76° C. and treated with 23.58 g (151.0 mmol, 1.11 equiv) of diisopropyl sulfide in 25 mL of tetrahydrofuran and the resulting mixture is stirred for 4 hours while slowly warming to room temperature. The reaction is poured onto 1.5 L of water and the aqueous mixture is extracted with diethyl ether (200 mL, 3x), treated with 400 g of ice, and acidified with concentrated hydrochloric acid. The resulting precipitate is collected by vacuum filtration and recrystallized from diethyl ether/cyclohexane to give 18.22 g (35.14 g theo., 52%) of analytically pure 3-isopropylthio-5-trimethylsilyl-2-furancarboxylic acid as a tan solid; mp 181°-183° C. is recooled to -76° C. the resulting mixture is stirred for 4 hours the aqueous mixture is extracted with diethyl ether (200 mL, 3x) treated with 400 g of ice The resulting precipitate is collected by vacuum filtration recrystallized from diethyl ether/cyclohexane

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of 25.01 g (136.0 mmol) of 5-trimethylsilyl-2-furancarboxylic acid (Carpenter, A. J. and Chadwick, D. J., Tetrahedron Lett., 26, 1777 (1985)) in 50 mL of dry tetrahydrofuran is added over 10 minutes to a -76° C. solution of freshly generated lithium diisopropylamide (328.0 mmol, 2.41 equiv) in dry tetrahydrofuran (175 mL) under nitrogen atmosphere and the resulting mixture is stirred at -76° to 65° C. for 1.5 hours. The reaction is recooled to -76° C. and treated with 23.58 g (151.0 mmol, 1.11 equiv) of diisopropyl sulfide in 25 mL of tetrahydrofuran and the resulting mixture is stirred for 4 hours while slowly warming to room temperature. The reaction is poured onto 1.5 L of water and the aqueous mixture is extracted with diethyl ether (200 mL, 3x), treated with 400 g of ice, and acidified with concentrated hydrochloric acid. The resulting precipitate is collected by vacuum filtration and recrystallized from diethyl ether/cyclohexane to give 18.22 g (35.14 g theo., 52%) of analytically pure 3-isopropylthio-5-trimethylsilyl-2-furancarboxylic acid as a tan solid; mp 181°-183° C. is recooled to -76° C. the resulting mixture is stirred for 4 hours the aqueous mixture is extracted with diethyl ether (200 mL, 3x) treated with 400 g of ice The resulting precipitate is collected by vacuum filtration recrystallized from diethyl ether/cyclohexane

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of 9.63 g (29.81 mmol) of 2-(4,5-dibromo-2-furanyl)-4,4-dimethyloxazoline in dry tetrahydrofuran (30 mL) is added dropwise to a -78° C. solution of freshly generated lithium diisopropylamide (33.89 mmol, 1.14 equiv) in tetrahydrofuran (80 mL) under an argon atmosphere. The resulting solution is stirred at -78° C. for 10 min and a solution of 5.49 g (46.49 mmol, 1.56 equiv) of isopropyl sulfide in tetrahydrofuran (20 mL) is added dropwise to the reaction. The reaction is stirred for 3.75 hr at -78° to -10° C. and poured onto 5% aqueous HCl (350 mL). The resulting aqueous solution is extracted with diethyl ether (4X). The combined organic extracts are washed with aqueous saturated NaCl, dried (Na2SO4), and concentrated in vacuo. Flash chromatography (SiO2, 7×25 cm, 10% CH2Cl2 /10% ethyl acetate/hexane) affords 7.67 g (11.84 g theo.; 65%) of the desired product as a yellow solid. Recrystallization from hexane affords an analytical sample; mp 71°-72° C. The reaction is stirred for 3.75 hr at -78° to -10° C. The resulting aqueous solution is extracted with diethyl ether (4X) The combined organic extracts are washed with aqueous saturated NaCl dried (Na2SO4) concentrated in vacuo

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of 25.01 g (136.0 mmol) of 5-trimethylsilyl-2-furancarboxylic acid (Carpenter, A. J. and Chadwick, D. J., Tetrahedron Lett., 26, 1777 (1985)) in 50 mL of dry tetrahydrofuran is added over 10 minutes to a -76° C. solution of freshly generated lithium diisopropylamide (328.0 mmol, 2.41 equiv) in dry tetrahydrofuran (175 mL) under nitrogen atmosphere and the resulting mixture is stirred at -76° to 65° C. for 1.5 hours. The reaction is recooled to -76° C. and treated with 23.58 g (151.0 mmol, 1.11 equiv) of diisopropyl sulfide in 25 mL of tetrahydrofuran and the resulting mixture is stirred for 4 hours while slowly warming to room temperature. The reaction is poured onto 1.5 L of water and the aqueous mixture is extracted with diethyl ether (200 mL, 3x), treated with 400 g of ice, and acidified with concentrated hydrochloric acid. The resulting precipitate is collected by vacuum filtration and recrystallized from diethyl ether/cyclohexane to give 18.22 g (35.14 g theo., 52%) of analytically pure 3-isopropylthio-5-trimethylsilyl-2-furancarboxylic acid as a tan solid; mp 181°-183° C. is recooled to -76° C. the resulting mixture is stirred for 4 hours the aqueous mixture is extracted with diethyl ether (200 mL, 3x) treated with 400 g of ice The resulting precipitate is collected by vacuum filtration recrystallized from diethyl ether/cyclohexane

Conditions: temp:0.00; pressure:0.00; stir: