反应详情

A solution of 8.7 g (0.04 mole) of crude 3-[4-(trifluoromethyl)phenoxy]azetidine in 75 ml of isopropyl ether was stirred under a blanket of nitrogen while 4.2 g (0.05 mole) of 2-propenyl isocyanate was added dropwise. After stirring for 3 days, no crystalline product precipitated. The reaction mixture was concentrated to a dark reddish oil. TLC (20% ethyl acetate/methylene chloride on silica gel) showed at least 6 spots, all well separated. The residue was dissolved in chloroform, chromatographed on a 350 g silica gel column and eluted with chloroform until the reddish forerun was removed. The column was then eluted with an ethyl acetate/chloroform gradient to 4% ethyl acetate. All the fractions were combined and concentrated to give 4.8 of orange oil, which crystallized on standing. Recrystallization from acetone/cyclohexane gave 3.3 g (27.5%) of being crystals, m.p. 91°-92.5° C.

1. additionwas added dropwise
2. customno crystalline product precipitated
3. concentrationThe reaction mixture was concentrated to a dark reddish oil
4. customall well separated
5. dissolutionThe residue was dissolved in chloroform
6. customchromatographed on a 350 g silica gel column
7. washeluted with chloroform until the reddish forerun
8. customwas removed
9. washThe column was then eluted with an ethyl acetate/chloroform gradient to 4% ethyl acetate
10. concentrationconcentrated
11. customto give 4.8 of orange oil, which
12. customcrystallized
13. customRecrystallization from acetone/cyclohexane
14. customgave 3.3 g (27.5%)