تفاعل #2507828
ord-63485a51519049168b72d9ac649dbebd
معادلة التفاعل
المتفاعلات
الكواشف
ظروف التفاعل
المعالجة
- 1استخلاصextracted three times with MTB ether
- 2غسيلphases are washed with water and sat. sodium chloride soln
- 3تجفيفand dried over sodium sulfate
- 4أخرىthe solvent is removed in vacuo
- 5أخرىthe residue is recrystallised from heptane at −25° C.
الإجراء التجريبي
15.5 g (51.5 mmol) of 7-bromo-6-fluoro-3-pentylchroman are dissolved in 85 ml of THF, and 35 ml (55.7 mmol) of a 15 percent solution of n-butyllithium in n-hexane are slowly added at −70° C. After 1 h, 6.3 ml (56.7 mmol) of N-formylpiperidine in 15 ml of THF are added dropwise, and the mixture is stirred for 1 h. The batch is subsequently allowed to thaw, added to water, acidified using dil. hydrochloric acid and extracted three times with MTB ether. The combined org. phases are washed with water and sat. sodium chloride soln. and dried over sodium sulfate, the solvent is removed in vacuo, and the residue is recrystallised from heptane at −25° C., giving 6-fluoro-3-pentylchroman-7-carbaldehyde as colourless crystals (Rf=0.4; 1-chlorobutane).