Реакция #985306

Уравнение реакции

3,3-Diethoxy-1-propyne

Cyclopropanecarboxylic acid methoxy-methyl-amide

n-butyllithium

hexane

→

yellowish oil

Выход 43.7%

1-Cyclopropyl-4,4-diethoxy-but-2-yn-1-one

Выход 43.7%

Растворители

THF

Условия реакции

Обработка

1. 1
   Температураto warm to −30° C.
2. 2
   Температураcooled again to −70° C
3. 3
   Другоеrose to −50°
4. 4
   workup.STIRRINGthen stirred
5. 5
   Температураwithout cooling until 0° C.
6. 6
   Другоеquenched with sat. NH4Cl solution (20 mL)
7. 7
   ЭкстракцияExtraction
8. 8
   ДругоеThe crude brown oil (15 g) was purified by chromatography on silica gel in heptane/ethyl acetate 10:1

Методика

3,3-Diethoxy-1-propyne (10 mL, 70 mmol) was dissolved under argon in THF (150 mL) and cooled to −70° C. Then a 1.6 M solution of n-butyllithium in hexane (48 mL, 77 mmol) was added slowly at −70° C., then allowed to warm to −30° C. and stirred at −30° C. for 30 min, then cooled again to −70° C. Cyclopropanecarboxylic acid methoxy-methyl-amide (10 g, 77 mmol) was added at once at −70° C. (the temperature rose to −50°) then stirred without cooling until 0° C. was reached, then quenched with sat. NH4Cl solution (20 mL). Extraction: 2×AcOEt, 1× sat. NH4Cl, 1× sat. NaCl. The crude brown oil (15 g) was purified by chromatography on silica gel in heptane/ethyl acetate 10:1. One obtained 6 g (43%) of a yellowish oil. MS: m/z=151(M).

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