Реакция #87949

Уравнение реакции

methyl cis-(1aRS,7bSR)-1,1-dibromo-5-methoxymethyl-1,1a,2,7b-tetrahydrocyclopropa[c]chromene-4-carboxylate

Intermediate 8

methyl cis-(1aRS,7bSR)-1,1-dibromo-5-methoxymethyl-1,1a,2,7b-tetrahydrocyclopropa[c]chromene-4-carboxylate

ammonium chloride

ammonium chloride

→

methyl cis-(1aRS,7bSR)-5-methoxymethyl-1,1a,2,7b-tetrahydrocyclopropa[c]chromene-4-carboxylate

Выход 97.2%

Растворители

ethanol

Условия реакции

Обработка

1. 1
   Температураheated
2. 2
   Температураat reflux for 6 hours
3. 3
   workup.STIRRINGthe mixture was stirred
4. 4
   Температураheated
5. 5
   Температураat reflux overnight
6. 6
   ТемператураAfter cooling
7. 7
   Фильтрацияthe mixture was filtered through Celite
8. 8
   Другоеthe filtrate was evaporated to dryness
9. 9
   ДругоеThe residue was partitioned between DCM and water
10. 10
    Сушкаthe organic layer was dried (MgSO4)
11. 11
    Фильтрацияfiltered
12. 12
    ДругоеThe filtrate was evaporated to dryness

Методика

A mixture of methyl cis-(1aRS,7bSR)-1,1-dibromo-5-methoxymethyl-1,1a,2,7b-tetrahydrocyclopropa[c]chromene-4-carboxylate (Intermediate 8, 1.06 g), zinc dust (4.14 g), and ammonium chloride (1.75 g) in absolute ethanol (100 mL) was stirred and heated at reflux for 6 hours. Further zinc dust (2.0 g) and ammonium chloride (0.9 g) were added and the mixture was stirred and heated at reflux overnight. After cooling, the mixture was filtered through Celite and the filtrate was evaporated to dryness. The residue was partitioned between DCM and water and the organic layer was dried (MgSO4) and filtered. The filtrate was evaporated to dryness to give methyl cis-(1aRS,7bSR)-5-methoxymethyl-1,1a,2,7b-tetrahydrocyclopropa[c]chromene-4-carboxylate (0.63 g) as an oil.

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