反应详情

To a stirred slurry of 11.4 g (0.3 mole) of lithium aluminum hydride (LAH) in 200 ml of freshly distilled (from LAH) tetrahydrofuran (THF) was added dropwise a solution of 57.3 g (0.2 mole) of 2-(4-chlorophenoxy)-1,3-propanedioic acid diethyl ester (C. A.59:5051f(1963); Mamaev and Mikhaleva, Isv.Sibirsk.Otd. Akad.Nauk. SSSR, 145-8 (1962)) in 150 ml of THF at such a rate that a gentle reflux was maintained. The mixture was stirred at ambient temperature for 5 hr and then the excess LAH was decomposed with successive, cautious, dropwise additions of 11.4 ml of water, 11.4 ml of a 15% sodium hydroxide solution, and 34 ml of water. A gelationous precipitate developed which was filtered through Celite with great difficulty. The filtrate was concentrated and the residue was purified by column chromatography on 500 g of silica gel eluted with 0-35% acetone in benzene. The appropriate fractions were combined and concentrated to give an oil which gradually crystallized. The solid was triturated with petroleum ether (30°-60° C.), collected by filtration, and dried to yield 18.2 g (45%) of white solid, mp 62°-64° C. (isopropyl ether).

1. temperaturea gentle reflux
2. temperaturewas maintained
3. filtrationwas filtered through Celite with great difficulty
4. concentrationThe filtrate was concentrated
5. customthe residue was purified by column chromatography on 500 g of silica gel
6. washeluted with 0-35% acetone in benzene
7. concentrationconcentrated
8. customto give an oil which
9. customgradually crystallized
10. customThe solid was triturated with petroleum ether (30°-60° C.)
11. filtrationcollected by filtration
12. customdried