2-but-3-enoxyoxane

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

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

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

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

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

Procedure: In a 500 ml rb flask were placed acrylic acid (2.85 g, 39.6 mmol) and Grubbs catalyst (1.68 g, 1.98 mmol) in anhydrous dichloromethane (200 ml). To this solution was added 2-but-3-enyloxy-tetrahydro-pyran (7.73 g, 49.50 mmol) and heated at refluxing for 12 hrs. The solvent was removed and the residue was purified on the column with Hexane/Ethyl acetate=100/5 to remove unchanged 2-but-3-enyloxy-tetrahydro-pyran. Then the column was eluted with Ethyl acetate/Methanol=100/1 to provide 6.66 g of a black oil (84%). 1H-NMR (DMSO-d6) δ 12.190 (s, 1H), 6.845-6.771 (m, 1H), 5.846-5.800 (d, 1H), 4.565-4.548 (t, 1H), 3.739-3.674 (m, 2H), 3.468-3.398 (m, 2H), 2.481-2.395 (m, 2H), 1.689-1.609 (m, 2H), 1.501-1.259 (m, 4H). In a 500 ml rb flask were placed heated at refluxing for 12 hrs The solvent was removed the residue was purified on the column with Hexane/Ethyl acetate=100/5 to remove unchanged 2-but-3-enyloxy-tetrahydro-pyran Then the column was eluted with Ethyl acetate/Methanol=100/1

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

Procedure: In a 1000 ml rb flask were placed 3-buten-1-ol (7.21 g, 100.00 mmol), 3,4-dihydro-2H-pyran (12.62 g, 150.00 mmol) and pyridinium p-toluenesulfonate (2.51 g, 10.00 mmol) in 350 ml of anhydrous dichloromethane. The reaction mixture was stirred at room temperature for 4 h. Then the reaction mixture was concentrated and the residue was purified by column with Hexane/Ethyl acetate=100/5 to provide 13.90 g of the desired product as an oil (89.0%). 1H-NMR (DMSO-d6) δ 5.851-5.742 (m, 1H), 5.103-5.011 (d, 1H), 4.997-4.985 (d, 1H), 4.555-4.537 (t, 1H), 3.745-3.611 (m, 2H), 3.433-3.347 (m, 2H), 2.290-2.236 (m, 2H), 1.698-1.675 (m, 2H), 1.611-1.566 (m, 4H). In a 1000 ml rb flask were placed Then the reaction mixture was concentrated the residue was purified by column with Hexane/Ethyl acetate=100/5

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

Procedure: A solution of n-butyllithium (12.0 ml, 30 mmol, 2.5 mol dm−3 in hexanes) was added dropwise to a stirred, cooled (−78° C.) solution of compound 2 (4.62 g, 30 mmol) in THF (60 ml) under an atmosphere of dry nitrogen. The reaction mixture was maintained at −78° C. for 1.5 h and a solution of allylchlorodimethylsilane (4.04 g, 30 mmol) in THF (20 ml) added dropwise. The reaction mixture was allowed to warm to room temperature, washed with water and the organic layer extracted into ethyl acetate/hexane (3 times). The combined extracts were washed with brine, dried (MgSO4) and the solvent removed in vacuo to yield a clear oil. The crude product was purified by column chromatography [silica gel, eluted with hexane/ethyl acetate (4:1), Rf: 0.48] to warm to room temperature washed with water the organic layer extracted into ethyl acetate/hexane (3 times) The combined extracts were washed with brine dried (MgSO4) the solvent removed in vacuo to yield a clear oil The crude product was purified by column chromatography [silica gel, eluted with hexane/ethyl acetate (4:1), Rf: 0.48]

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

Procedure: A solution of phosphoryl chloride (0.5 ml in 10 ml of DCM) was added with care to a solution of but-2-yn-1-ol (8.75 g, 125 mmol) and dihydropyran (10.50 g, 125 mmol) in DCM (80 ml). The reaction mixture was stirred at room temperature for 16 h, washed with sodium hydrogen carbonate solution (3 times), dried (MgSO4) and the solvent removed in vacuo to yield a colorless oil. The crude product was purified by column chromatography [silica gel, euted with hexane/ethyl acetate (4:1), Rf: 0.36] to yield a colorless oil. washed with sodium hydrogen carbonate solution (3 times) dried (MgSO4) the solvent removed in vacuo to yield a colorless oil The crude product was purified by column chromatography [silica gel, euted with hexane/ethyl acetate (4:1), Rf: 0.36] to yield a colorless oil

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

Procedure: Into a 500-mL flask containing 2-(3-butenyloxy)tetrahydropyran (49.0 g, 0.314 mol) in CH2Cl2 (500 mL) under a nitrogen atmosphere and cooled to 0° C. was added freshly crystallized m-chloroperoxybenzoic acid (95 g, 0.55 mol). The mixture was maintained at 0° C. for a period of 24 h. The precipitated benzoic acid was removed via vacuum filtration. The filtrate thus obtained was washed successively with 10% aqueous sodium hydroxide (500 mL) and saturated aqueous sodium sulfite (500 mL), respectively, the organic layer dried over anhydrous MgSO4 and concentrated in vacuo to afford tetrahydro-2-(oxiranylethoxy)-2H-pyran as a pure clear colorless liquid (52 g, 95%), which was used without any further purification: 1H NMR (CDCl3, 300 MHz) δ 4.62 (s, 1H], 3.86-3.92 [m, 2H], 3.52-3.55 [m, 2H], 3.08 [br, 1H], 2.78-2.81 [t, J=3 Hz, 1H], 2.53-2.55 [t, J=3 Hz, 1H], 1.53-1.88 [m, 8H]. The mixture was maintained at 0° C. for a period of 24 h The precipitated benzoic acid was removed via vacuum filtration The filtrate thus obtained was washed successively with 10% aqueous sodium hydroxide (500 mL) and saturated aqueous sodium sulfite (500 mL) respectively, the organic layer dried over anhydrous MgSO4 concentrated in vacuo

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

Procedure: To a chilled solution (0° C.) of 3,4-dihydro-2H-pyran (117 g, 1.4 mol) in anhydrous ether (600 mL) were added p-toluensulfonic acid (0.5 g) and 3-buten-1-ol (25.0 g, 0.35 mol). The resulting mixture was stirred at room temperature for 5 h and was then quenched by the addition of concentrated ammonium hydroxide (5 mL) and methanol (50 mL). The solvent was evaporated in vacuo, and ether was added to the residue. The precipitated ammonium p-toluenesulfate was filtered, the filtrate was concentrated, and the crude product was purified by flash column chromatography on silica gel (0-5% ethyl acetate in hexanes) to give 2-(3-butenyloxy)tetrahydropyran (49 g, 90%) as colorless viscous liquid: 1H-NMR (CDCl3, 300 MHz,) δ 5.80-5.89 [m, 1H, ═CH—C], 5.02-5.06 [m overlapping, 2H, ═CH2], 4.59-4.60 [m, 1H, 2-H of THP], 3.77-3.83 [m, 2H, —CH2O], 3.44-3.50 [m, 2H, CH2O of THP], 2.33-2.38 [m, 2H, CH2—CH═CH2], 1.51-1.71 [m, 6H, Hs of THP]. was then quenched by the addition of concentrated ammonium hydroxide (5 mL) and methanol (50 mL) The solvent was evaporated in vacuo, and ether was added to the residue The precipitated ammonium p-toluenesulfate was filtered the filtrate was concentrated the crude product was purified by flash column chromatography on silica gel (0-5% ethyl acetate in hexanes)

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