Hydrochloric Acid → 1-Bromo-4-cyclopropoxybenzene

The following cyclopropanation was conducted according to the description in the document (Tetrahedron Lett., (1998), 39, 8621-8624). Diethylzinc (1.0 M n-hexane solution, 250 mL, 250 mmol) was added to methylene chloride (250 mL), and a methylene chloride (120 mL) solution of trifluoroacetic acid (19.2 mL, 249 mmol) was added thereto under ice-cooling over 100 minutes. The mixture was further stirred for 1 hour. Then, a methylene chloride (100 mL) solution of chloroiodomethane (20.1 mL, 250 mmol) was added thereto under ice-cooling over 40 minutes. At the same temperature, a methylene chloride (120 mL) solution of 1-bromo-4-(vinyloxy)benzene (32.8 g, 165 mmol) prepared in Example 5 (5b) was added thereto over 20 minutes. The resulting mixture was stirred at room temperature for 1.5 hours. To the reaction solution was added 0.1 N hydrochloric acid (400 mL). The mixture was stirred for 30 minutes, filtered through Celite, and further washed with n-hexane (200 mL). The filtrate and the n-hexane washing solution were combined, and the organic layer was washed with 0.1 N hydrochloric acid (100 mL) and saturated brine (100 mL) containing about 1 g of sodium sulfite twice. This organic layer was dried over anhydrous magnesium sulfate, and then the solvent was evaporated to give 36.0 g of 1-bromo-4-(cyclopropyloxy)benzene (yellow oil).

1. temperatureunder ice-cooling over 100 minutes
2. temperatureunder ice-cooling over 40 minutes
3. waitover 20 minutes
4. stirringThe resulting mixture was stirred at room temperature for 1.5 hours
5. stirringThe mixture was stirred for 30 minutes
6. filtrationfiltered through Celite
7. washfurther washed with n-hexane (200 mL)
8. washthe organic layer was washed with 0.1 N hydrochloric acid (100 mL) and saturated brine (100 mL)
9. additioncontaining about 1 g of sodium sulfite twice
10. dry with materialThis organic layer was dried over anhydrous magnesium sulfate
11. customthe solvent was evaporated

ORD record

ord-7c97fdc2980d401ead1c646f31435519

Source dataset

uspto-grants-2013_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08344029B2