Chloromethyl Methyl Ether → 2,3-Dihydro-6-bromo-5-benzofuranol methoxymethyl ether

A flame-dried 1000 mL 3-neck flask fitted with an internal thermometer, magnetic stirring, and a 250 mL dropping funnel was charged with sodium hydride (60% dispersion in mineral oil, 11.17 g, 279 mmol) and dimethylformamide (dried over molecular sieves, 200 mL). A solution of 16 (50.00 g, 233 mmol) in dimethylformamide (100 mL) was added dropwise such that the reaction temperature did not exceed 40° C (addition time was approximately 30 minutes). When hydrogen evolution had ceased, an ice bath was added and chloromethyl methylether (22.47 g, 297 mmol) was added dropwise at 25° C. Upon completion of the addition the reaction mixture was allowed to stir at room temperature for two hours then quenched by pouring into water (1000 mL). The mixture was extracted with ether (3×300 mL) and the combined organic extracts washed sequentially with water (2×500 mL) and 20% NaCl (300 mL), dried (Na2SO4), and concentrated. Distillation afforded 17 as a colorless liquid.

1. customA flame-dried 1000 mL 3-neck flask fitted with an internal thermometer, magnetic stirring
2. customdid not exceed 40° C
3. addition(addition time was approximately 30 minutes)
4. additionan ice bath was added
5. additionUpon completion of the addition the reaction mixture
6. customthen quenched
7. additionby pouring into water (1000 mL)
8. extractionThe mixture was extracted with ether (3×300 mL)
9. washthe combined organic extracts washed sequentially with water (2×500 mL) and 20% NaCl (300 mL)
10. dry with materialdried (Na2SO4)
11. concentrationconcentrated
12. distillationDistillation

ORD-Eintrag

ord-3dbd77bf5071415486dd0f927592ddcb

Quelldatensatz

uspto-grants-1990_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US04966907