تفاعل #1945
ord-05fc3ca2347f436aa6a5c4b9b479ce81
معادلة التفاعل
الكواشف
ظروف التفاعل
المعالجة
- 1workup.STIRRINGAfter the reaction mixture was stirred at -60° C. for 0.5 hours
- 2أخرىwas allowed to slowly (1.5 hours)
- 3درجة الحرارةwarm to -30° C
- 4غسيلeluted with 5% methanol in methylene chloride
- 5workup.ADDITIONThe reaction mixture was poured into cold brine
- 6استخلاصthe aqueous mixture was extracted with methylene chloride
- 7استخلاصThe organic extract
- 8تجفيفwas dried over anhydrous sodium sulfate
- 9ترشيحfiltered
- 10تركيزconcentrated in vacuo
- 11workup.DISTILLATIONThe residue was distilled
الإجراء التجريبي
A 1.5M solution of LDA in hexane (100 mL, 150 mmol) was cooled to -60° C. in an isopropyl alcohol/dry ice bath. To the stirred LDA solution, under nitrogen, was added, dropwise over a 0.5 hours period, a solution of 17.466 g (137 mmol) of 4-chloro-2-picoline (the product of Step 1 of Example 58) in 80 mL of dry THF. The reaction mixture was stirred for 0.5 hours at -60° C. and then a solution of 10.95 mL (137 mmol) of ethyl iodide in 30 mL of dry THF was added, dropwise over a 20 minute period. After the reaction mixture was stirred at -60° C. for 0.5 hours, the cooling bath was allowed to slowly (1.5 hours) warm to -30° C. According to TLC analysis on silica gel eluted with 5% methanol in methylene chloride, the reaction had gone to completion. The reaction mixture was poured into cold brine and the aqueous mixture was extracted with methylene chloride. The organic extract was dried over anhydrous sodium sulfate, filtered and concentrated in vacuo. The residue was distilled to afford 12.667 g (60% yield of the title compound, b.p. 77°-80° C. (10 mm Hg).