反应详情

A 1M solution of DIBAL-H in toluene (42 ml, 42 mmol) was added dropwise, at −70° C. over 30 min, to a stirred solution of (E)-ethyl 3-(4-bromophenyl)-but-2-enoate (4.55 g, 16.92 mmol) in dry THF (100 ml), and the mixture stirred for 1 h. Methanol (5 ml) was carefully added, followed by 1N HCl (300 ml) and the resulting mixture extracted with ethyl acetate (3×200 ml). The combined organic extracts were washed with brine, dried (Na2SO4), and evaporated to give the crude product as an off-white solid, which was purified by recrystallisation from hot 1:4 ether/n-heptane (250 ml) to give the product (E)-3-(4-bromophenyl)-but-2-en-1-ol as colourless needles: 3.10 g (81%)

1. extractionthe resulting mixture extracted with ethyl acetate (3×200 ml)
2. washThe combined organic extracts were washed with brine
3. dry with materialdried (Na2SO4)
4. customevaporated
5. customto give the crude product as an off-white solid, which
6. customwas purified by recrystallisation from hot 1:4 ether/n-heptane (250 ml)