Реакция #321435

Уравнение реакции

4-Formylamino-2,3,5-trimethyl-6-(2-methyl-2-propenyl)phenol

sodium acetate

Bromine

→

desired compound

Выход 67.1%

2-Bromomethyl-5-formylamino-2,4,6,7-tetramethyl-2,3-dihydrobenzofuran

Выход 67.1%

Растворители

acetic acid

Условия реакции

Обработка

1. 1
   workup.STIRRINGAfter the reaction mixture was stirred for 30 minutes
2. 2
   Экстракцияthe product was extracted with ethyl acetate
3. 3
   ПромывкаThe extract was washed with aqueous saturated sodium bicarbonate solution
4. 4
   Другоеdried
5. 5
   Концентрированиеconcentrated
6. 6
   workup.DISSOLUTIONThe residue was dissolved in ethyl acetate again
7. 7
   Фильтрацияinsoluble materials were filtered off
8. 8
   КонцентрированиеThe filtrate was concentrated
9. 9
   workup.ADDITIONisopropyl ether was added to the residue
10. 10
    ДругоеThe crystals precipitated
11. 11
    Фильтрацияwere filtered off

Методика

4-Formylamino-2,3,5-trimethyl-6-(2-methyl-2-propenyl)phenol (50 g, 0.21 mol) and sodium acetate (30.5 g, 0.37 mol) were added to acetic acid (500 ml). Bromine (16.5 ml, 0.21 mol) was added dropwise to the mixture with stirring. After the reaction mixture was stirred for 30 minutes, the mixture was poured into ice water and the product was extracted with ethyl acetate. The extract was washed with aqueous saturated sodium bicarbonate solution, dried and then concentrated. The residue was dissolved in ethyl acetate again and insoluble materials were filtered off. The filtrate was concentrated and isopropyl ether was added to the residue. The crystals precipitated were filtered off to obtain the desired compound (44.0 g, yield: 65.7%), m.p. 157°-158° C.

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