5-(oxan-2-yloxy)pentan-1-ol

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a mixture of pentane-1,5-diol(5.2 g, 0.05 mol) and p-toluenesulfonic acid (0.1 g, 0.53 mmol) in CH2Cl2 (120 mL) was added slowly dihydro-2H-pyran (4.6 g, 0.055 mol) in CH2Cl2 (30 mL) at 0° C. After stirring for 2 h at 0° C. and for another 1 h at room temperature, saturated NaHCO3 (50 mL) was added to the reaction mixture. The CH2Cl2 layer was washed with saturated NaHCO3 (50 mL), water (50 mL), and dried (MgSO4). The residue was purified by column chromatography on silica gel with EtOAc:hexane (1:1, v/v) and subsequent Kugelrohr distillation to give the title product (4, 5.1 g, 54%); bp 80° C.-85° C./0.1 torr; IR(neat): 3450 (broad) and 1135 cm-1 :1H NMR: 1.3-1.9 (m, 12H), 2.4 (b s, lH), 3.3-3.9 (m, 6H), and 4.58 ppm (m, IH). The CH2Cl2 layer was washed with saturated NaHCO3 (50 mL), water (50 mL) dried (MgSO4) The residue was purified by column chromatography on silica gel with EtOAc:hexane (1:1 v/v) and subsequent Kugelrohr distillation

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

Procedure: To 31.2 g of 1.5-pentanediol was added 380 mg of p-toluenesulfonic acid monohydride and dropwise 8.4 g of dihydropyran with ice-cooling and stirring over 20 minutes, and the mixture was stirred at a room temperature for 3.5 hours. After adding 300 ml of chloroform, the mixture was washed with 2% sodium bicarbonate aqueous solution, water and a saturated sodium chloride aqueous solution, dried over magnesium sulfate, filtered and evaporated under a reduced pressure. The residue was applied to a silica gel column and eluted with hexane/ethyl acetate (3:1) to obtain 6.0 g of 2-(5-hydroxypentyloxy)tetrahydropyran as a colorless liquid. cooling the mixture was stirred at a room temperature for 3.5 hours the mixture was washed with 2% sodium bicarbonate aqueous solution, water a saturated sodium chloride aqueous solution, dried over magnesium sulfate filtered evaporated under a reduced pressure eluted with hexane/ethyl acetate (3:1)

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a mixture of pentane-1,5-diol(5.2 g, 0.05 mol) and p-toluenesulfonic acid (0.1g, 0.53 mmol) in CH2Cl2 (120 mL) was added slowly dihydro-2H-pyran (4.6 g, 0.055 mol) in CH2Cl2 (30 mL) at 0° C. After stirring for 2 h at 0° C. and for another 1 h at room temperature, saturated NaHCO3 (50 mL ) was added to the reaction mixture. The CH2Cl2 layer was washed with saturated NaHCO3 (50 mL), water (50 mL), and dried (MgSO4). The residue was purified by column chromatography on silica gel with EtOAc:hexane (1:1, v/v) and subsequent Kugelrohr distillation to give the title product (4, 5.1 g, 54%); bp 80°-85° C./0.1 torr; IR(neat): 3450 (broad) and 1135 cm-1 ; 1H NMR: 1.3-1.9 (m, 12H), 2.4 (b s, 1H ), 3.3-3.9 ( m, 6H ), and 4.58 ppm (m, 1H ). The CH2Cl2 layer was washed with saturated NaHCO3 (50 mL), water (50 mL) dried (MgSO4) The residue was purified by column chromatography on silica gel with EtOAc:hexane (1:1 v/v) and subsequent Kugelrohr distillation

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a mixture of pentane-1,5-diol(5.2 g, 0.05 mol) and p-toluenesulfonic acid (0.1 g, 0.53 mmol) in CH2Cl2 (120 mL) was added slowly dihydro-2H-pyran (4.6 g, 0.055 mol) in CH2Cl2 (30 mL) at 0° C. After stirring for 2 h at 0° C. and for another 1 h at room temperature, saturated NaHCO3 (50 mL) was added to the reaction mixture. The CH2Cl2 layer was washed with saturated NaHCO3 (50 mL), water (50 mL), and dried (MgSO4). The residue was purified by column chromatography on silica gel with EtOAc:hexane (1:1, v/v) and subsequent Kugelrohr distillation to give the title product (4, 5.1 g, 54%); bp 80° C.-85° C./0.1 torr; IR(neat): 3450 (broad) and 1135 cm-1 :1H NMR: 1.3-1.9 (m, 12H), 2.4 (b s, lH), 3.3-3.9 (m, 6H), and 4.58 ppm (m, IH). The CH2Cl2 layer was washed with saturated NaHCO3 (50 mL), water (50 mL) dried (MgSO4) The residue was purified by column chromatography on silica gel with EtOAc:hexane (1:1 v/v) and subsequent Kugelrohr distillation