2,5-二羟甲基四氢呋喃

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

实验步骤: In a similar fashion, 3,4-dideoxy-threo-hexitol was dehydrated in the presence of sulfuric acid catalyst to give cis-2,5-bis(hydroxymethyl)tetrahydrofuran; di-p-toluenesulfonate, m.p. 128°-129° C., reported m.p. 128°-130° C. (Cope and Baxter, J. Am. Chem. Soc., 77, 393-396 (1955)).

反应条件: temp:100.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A suspension of 2.64 g (20 mmol) of cis-2,5-bis(hydroxymethyl)tetrahydrofuran, 7.99 g (24 mmol) of octadecyl bromide, 2.43 g (30 mmol) of potassium cyanate and 0.966 g (3 mmol) of tetrabutyl ammonium bromide in 100 ml of dry acetonitrile was refluxed, with stirring, at 100° C. for 20 hours. The resultant mixture was then diluted with hot methylene chloride, filtered and the filtrate concentrated in vacuo. The crude product was then purified by flash silica gel chromatography employing successive mixtures of petroleum ether and ethyl acetate in ratios of 4:1, 2.33:1 and 1:1 as the eluent to yield the title compound as a solid, m.p. 79°-80° C. was refluxed filtered the filtrate concentrated in vacuo The crude product was then purified by flash silica gel chromatography

反应条件: temp:5.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: To a three-neck flask equipped with a thermometer, reflux condenser, mechanical stirrer, and dropping funnel a solution of 924 grams (7 moles) of cis-2,5-bis-(hydroxymethyl) tetrahydrofuran, represented by formula (I), in 900 ml of pyridine was placed and cooled at 5° C. A solution of 2669 grams (14 moles) of p-toluenesulfonyl chloride in 4 liters of pyridine was added slowly through the dropping funnel. The temperature during the addition was kept below 10°-15° C. After the addition of p-toluenesulfonyl chloride, the reaction mixture was stirred for 2 hours and then let stand at room temperature overnight. The reaction mixture was poured over ice-water and the product precipitated. The ditosylate, represented by formula (II), was filtered off and washed several times with water and dried. The product obtained had a melting point of 125°-126.5° C. To a three-neck flask equipped with a thermometer reflux condenser, mechanical stirrer The temperature during the addition was kept below 10°-15° C let stand at room temperature overnight the product precipitated was filtered off washed several times with water dried The product obtained

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

实验步骤: In a similar fashion, 3,4-dideoxy-threo-hexitol was dehydrated in the presence of sulfuric acid catalyst to give cis-2,5-bis(hydroxymethyl)tetrahydrofuran; di-p-toluenesulfonate, m.p. 128°-129° C., reported m.p. 128°-130° C. (Cope and Baxter, J. Am. Chem. Soc., 77, 393-396 (1955)).