反应详情

温度

-60 °C

2-phenyl-1,3-dithiane (Aldrich) (3.79 g; 19.3 mmol) was mixed with dry distilled THF (20 mL) under a nitrogen atmosphere. The solution was cooled to −60° C. and n-butyl lithium (1.6M in pentane, 1.56 mmol, 9.74 mL) was added slowly by syringe. The reaction mixture was warmed to −20° C. and held at that temperature for 30 minutes, and then held at −10° C. for 15 minutes. The yellow solution was cooled to −78° C. and (1-Formyl-pentyl)-carbamic acid tert-butyl ester (1.6 g, 1.4 mmol, in 5 ml THF) was added rapidly (over 20 seconds) and 60 seconds later a mixture of 2 mL acetic acid and 5 mL THF was added rapidly. After warming to 23° C. the solution was concentrated at reduced pressure. Excess 2-phenyl-1,3-dithiane was removed by its crystallization away from the desired product using a minimum of ethyl acetate in hexane. The mother liquors were concentrated and chromatographed using a hexane-ethyl acetate gradient to afford 1.7 g of {1-[Hydroxy-(2-phenyl-[1,3]dithian-2-yl)-methyl]-pentyl}-carbamic acid tert-butyl ester. (56% yield).

1. customwith dry
2. distillationdistilled THF (20 mL) under a nitrogen atmosphere
3. temperatureThe reaction mixture was warmed to −20° C.
4. waitheld at −10° C. for 15 minutes
5. temperatureThe yellow solution was cooled to −78° C.
6. additionwas added rapidly
7. temperatureAfter warming to 23° C. the solution
8. concentrationwas concentrated at reduced pressure
9. customExcess 2-phenyl-1,3-dithiane was removed by its crystallization away from the desired product
10. concentrationThe mother liquors were concentrated
11. customchromatographed