2,5-二甲基呋喃

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 2,5-Dimethylfuran (2.3 ml, 21.6 mmol) and magnesium iodide (0.40 g, 1.4 mmol) are added to a solution of 2-(5-bromo-2-ethylphenyl)cyclopent-4-ene-1,3-dione (2.0 g, 7.2 mmol) in dichloromethane (10 ml) and the mixture is stirred at room temperature for 3 days. The reaction mixture is concentrated under reduced pressure and the residue is purified by column chromatography on silica gel to give (1RS,2SR,6RS,7SR)-4-(5-bromo-2-ethylphenyl)-1,7-dimethyl-10-oxatricyclo[5.2.1.02,6]dec-8-en-3,5-dione. The reaction mixture is concentrated under reduced pressure the residue is purified by column chromatography on silica gel

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 2,5-dimethyl-furan-3-sulfonylchloride was prepared by the method of Example 40B with DMF (28 mmoles, 2.2 ml), sulfurylchloride (24 mmoles, 1.9 ml) and 2,5-dimethyl-furan (14 mmoles, 1.5 ml). Flash chromatography (5% ethyl acetate/hexanes) provided 0.61 g (22%) of a yellow liquid.

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 2,5-Dimethylfuran (2.3 ml, 21.6 mmol) and magnesium iodide (0.40 g, 1.4 mmol) are added to a solution of 2-(5-bromo-2-ethylphenyl)cyclopent-4-ene-1,3-dione (2.0 g, 7.2 mmol) in dichloromethane (10 ml) and the mixture is stirred at room temperature for 3 days. The reaction mixture is concentrated under reduced pressure and the residue is purified by column chromatography on silica gel to give (1RS,2SR,6RS,7SR)-4-(5-bromo-2-ethylphenyl)-1,7-dimethyl-10-oxatricyclo[5.2.1.02,6]dec-8-en-3,5-dione. The reaction mixture is concentrated under reduced pressure the residue is purified by column chromatography on silica gel

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 2,5-Dimethylfuran (2.3 ml, 21.6 mmol) and magnesium iodide (0.40 g, 1.4 mmol) are added to a solution of 2-(5-bromo-2-ethylphenyl)cyclopent-4-ene-1,3-dione (2.0 g, 7.2 mmol) in dichloromethane (10 ml) and the mixture is stirred at room temperature for 3 days. The reaction mixture is concentrated under reduced pressure and the residue is purified by column chromatography on silica gel to give (1RS,2SR,6RS,7SR)-4-(5-bromo-2-ethylphenyl)-1,7-dimethyl-10-oxatricyclo[5.2.1.02,6]dec-8-en-3,5-dione. The reaction mixture is concentrated under reduced pressure the residue is purified by column chromatography on silica gel

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 2,5-dimethyl-furan-3-sulfonylchloride was prepared by the method of Example 40B with DMF (28 mmoles, 2.2 ml), sulfurylchloride (24 mmoles, 1.9 ml) and 2,5-dimethyl-furan (14 mmoles, 1.5 ml). Flash chromatography (5% ethyl acetate/hexanes) provided 0.61 g (22%) of a yellow liquid.

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 2,5-dimethyl-furan-3-sulfonylchloride was prepared by the method of Example 40B with DMF (28 mmoles, 2.2 ml), sulfurylchloride (24 mmoles, 1.9 ml) and 2,5-dimethyl-furan (14 mmoles, 1.5 ml). Flash chromatography (5% ethyl acetate/hexanes) provided 0.61 g (22%) of a yellow liquid.

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 2,5-dimethyl-furan-3-sulfonylchloride was prepared by the method of Example 40B with DMF (28 mmoles, 2.2 ml), sulfurylchloride (24 mmoles, 1.9 ml) and 2,5-dimethyl-furan (14 mmoles, 1.5 ml). Flash chromatography (5% ethyl acetate/hexanes) provided 0.61 g (22%) of a yellow liquid.

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: In another aspect, the present disclosure provides a method C for preparing 2,5-dimethylfuran, which includes the steps of: a) combining 5-(hydroxymethyl)furfural (HMF) with H2, a first catalyst, and an aprotic solvent; b) reacting the mixture of step (a) to form 2,5-bis(hydroxymethyl)furan (BHMF); c) adding a carboxylic acid, and a second catalyst to the reaction mixture of step (b) to form an ester of BHMF; and d) adding H2 to the reaction mixture that includes the ester of BHMF of step (c) to form 2,5-dimethylfuran. In another aspect, the present disclosure provides a method C

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: In another aspect, the present disclosure provides a method for preparing 2,5-dimethylfuran, which includes the steps of: a) combining 5-(hydroxymethyl)furfural (HMF) with H2, a first catalyst, and an aprotic solvent; b) reacting the mixture of step (a) to form 2,5-bis(hydroxymethyl)furan (BHMF); c) adding a carboxylic acid, and a second catalyst to the reaction mixture of step (b) to form an ester of BHMF; and d) adding H2 to the reaction mixture that includes the ester of BHMF of step (c) to form 2,5-dimethylfuran. In another aspect, the present disclosure provides a method

反应条件: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A slurry of 4-(2,5-Dioxo-2,5-dihydro-pyrrol-1-yl)-2-trifluoromethyl-benzonitrile (30 g, 113 mmol) and 2,5-dimethylfuran (70 mL) was stirred at 60° C. for 0.5 h. After toluene (40 mL) was added, the reaction mixture was stirred at 60° C. for 3 h. The mixture was then cooled in ice bath. The solid was collected by filtration and washed with cold toluene (30 mL) to give Preparation 1 as an off white solid (36.8 g, 102 mmol, 90% yield). The mixture was then cooled in ice bath The solid was collected by filtration washed with cold toluene (30 mL) to give

反应条件: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: DMF (2.2 ml, 28 mmol) and sulfuryl chloride (1.9 ml, 24 mmol) were stirred at 0° C. for 30 minutes and then the 2,5-dimethylfuran (1.5 ml, 14 mmol) was slowly added. The reaction mixture was heated to 60° C. for 30 minutes, then cooled to ambient temperature and poured into ice water (200 ml). The aqueous layer was extracted with EtOAc (100 ml) and then the organic layer was dried (MgSO4) filtered and concentrated to collect 0.69 g of a brown liquid. Flash chromatography (5% EtOAc/hexane) provided 0.607 g (22% yield) of a yellow liquid. cooled to ambient temperature The aqueous layer was extracted with EtOAc (100 ml) the organic layer was dried (MgSO4) filtered concentrated to collect 0.69 g of a brown liquid

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A 100 mL 3-necked RBF is fitted with a mechanical stirrer, a condenser and a subaseal, and placed under nitrogen. Maleic anhydride (25.5 g, 0.260 mol) and anhydrous diethyl ether (35 mL) are charged to the RBF. 2,5-Dimethylfuran (27.7 mL, 0.260 mol) is added via syringe over a period of 20 mins to the suspension at 22° C. The reaction mixture is stirred for 18 h. The product is filtered off, washed with cold diethyl ether (100 mL), and dried under vacuum to yield the product 1 as a cream solid (36.32 g, 72%): 1H-NMR (300 MHz, CDCl3) δ6.35 (s, 2H), 3.16 (s, 2H), 1.76 (s, 6H). A 100 mL 3-necked RBF is fitted with a mechanical stirrer, a condenser The product is filtered off washed with cold diethyl ether (100 mL) dried under vacuum