反应详情

Compound (31) obtained according to section (A) (15.6 g, 0.1 mole) was added at 0° C. to 150 ml of pyridine-benzene mixture (1:1), and while being stirred, the solution was added to 9.0 g (0.033 mole) of PBr3. The reaction mixture was stirred for 2 hours at 0° C. and then 2 hours at room temperature, poured over ice/2 N HCl and extracted with diethyl ether. The ether extract was washed once each with 2 N HCl, 2 N NaOH, and NaCl solution, dried with Na2SO4, and concentrated. The bromide of formula (32) was purified chromatographically with silica gel.

1. stirringThe reaction mixture was stirred for 2 hours at 0° C.
2. extractionextracted with diethyl ether
3. extractionThe ether extract
4. washwas washed once each with 2 N HCl, 2 N NaOH, and NaCl solution
5. dry with materialdried with Na2SO4
6. concentrationconcentrated
7. customThe bromide of formula (32) was purified chromatographically with silica gel