反应详情

The title compound was prepared by a modification of the procedure of Przybilla, described in German Patent No. DE4207261A1 (Sep. 9, 1993), herein incorporated by reference. The (4-vinylphenyl)magnesium bromide solution of Example 1 was cooled to −40 to −30° C. using a dry ice/acetone bath. Subsequently, hexafluoroacetone was introduced below the surface until an excess was achieved (weight added 62 g, 373.45 mmol). The reaction mixture was stirred in the cooling bath for 15 min, then placed in an ice-bath for an additional 15 min, and finally poured into cold 1N H2SO4 (1000 mL). The aqueous solution was extracted with ether, and the combined extracts were washed with brine, dried (Na2SO4), and concentrated to provide 101.60 g of a pale yellow oil. This material was purified by vacuum distillation to provide 52.43 g (73%) of a colorless oil: bp 55-6° C. (1.3 mm); 1H NMR (CDCl3) δ 7.69 (d, 2ArH), 7.50 (d, 2ArH), 6.75 (dd, CH═), 5.84 (dd, ═CHH), 5.36 (dd, ═CHH), 3.73 (s, OH),+9% THF.

1. addition(weight added 62 g, 373.45 mmol)
2. waitplaced in an ice-bath for an additional 15 min
3. extractionThe aqueous solution was extracted with ether
4. washthe combined extracts were washed with brine
5. dry with materialdried (Na2SO4)
6. concentrationconcentrated