p-Anisoyl chloride → HCID 2758698, compound

2-(2-Bromoethyl)-1,3-dioxolane (45 ml) was added dropwise within 15 minutes under argon and while stirring at a maximum 30° C. to a suspension of Rieke magnesium, prepared from 51.2 g of magnesium chloride, in 1300 ml of absolute tetrahydrofuran. The suspension was stirred at room temperature for 15 minutes, cooled to 0° C. and, after the addition of 49.6 g of copper(I) bromide, stirred at 5° C. for 15 minutes. After cooling to -70° C. 50.0 g of p-anisoyl chloride dissolved in 150 ml of absolute tetrahydrofuran were added dropwise within 20 minutes. The reaction mixture was stirred at -70° C. for 30 minutes and at room temperature for 2 hours and subsequently hydrolyzed with 800 ml of saturated ammonium chloride solution while cooling at a maximum 30° C. After the addition of 500 ml of water the mixture was extracted three times with 700 ml of ethyl acetate each time. The combined organic extracts were washed with 1000 ml of saturated sodium chloride solution, dried over MgSO4 and freed from solvent. 82.4 g of dark brown oil were chromatographed on 2000 g of silica gel with ethyl acetate/hexane (1:1) as the eluent. 48.8 g (71%) of 3-(1,3-dioxolan-2-yl)-4'-methoxypropiophenone were isolated as a yellow-orange oil.

1. temperaturecooled to 0° C.
2. stirringstirred at 5° C. for 15 minutes
3. temperatureAfter cooling to -70° C
4. additionwere added dropwise within 20 minutes
5. temperaturewhile cooling at a maximum 30° C
6. extractionwas extracted three times with 700 ml of ethyl acetate each time
7. washThe combined organic extracts were washed with 1000 ml of saturated sodium chloride solution
8. dry with materialdried over MgSO4
9. custom82.4 g of dark brown oil were chromatographed on 2000 g of silica gel with ethyl acetate/hexane (1:1) as the eluent

ORD record

ord-0f73710f8f77464ca67746d7120ae38a

Source dataset

uspto-grants-1994_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05292732