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 (CA 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 gelatinous 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