反应详情

0.585 g (2.07 mmol) of the above synthesized 5-(4-trifluoromethyl-phenyl)-pyrazine-2-carboxylic acid methyl ester in 10 ml of abs. THF was cooled down to −30° C. and reacted with 5.18 ml of DIBAL-H-solution (1.2 M in toluene, 3 eq.) for 10 min. The reaction was warmed up during 2.5 h to 10° C. and stirred 1 h at RT. Careful quenching at 0° C. with saturated NaCl solution, twofold extraction with ether, washing with brine, drying over sodium sulfate, and evaporation of the solvents left a crude product which was purified by flash chromatography (SiO2, heptane/AcOEt=4/1) to deliver finally 0.325 g of the title compound as yellow solid.

1. temperatureThe reaction was warmed up during 2.5 h to 10° C.
2. customCareful quenching at 0° C. with saturated NaCl solution
3. extractionextraction with ether
4. washwashing with brine
5. dry with materialdrying over sodium sulfate, and evaporation of the solvents
6. waitleft a crude product which
7. customwas purified by flash chromatography (SiO2, heptane/AcOEt=4/1)