Methyl iodide → HCID 21803382, compound

Temperature

0 °C

A 1.6N solution of n-butyllithium in n-hexane was added dropwise within 15 minutes at -70° C. under argon and while stirring to a solution of 7.1 ml of diisopropylamine in 200 ml of absolute tetrahydrofuran. The reaction mixture was stirred at 0° C. for 15 minutes, then again cooled to -70° C., treated with 30 ml of hexamethylphosphoric acid triamide and 9.5 g of 3-(1,3-dioxolan-2-yl)propiophenone, dissolved in 10 ml of absolute tetrahydrofuran and stirred for 15 minutes. After the addition of 3.2 ml of methyl iodide at -70° C. the mixture was brought to room temperature and stirred for 2 hours. The reaction solution was poured on to 100 ml of saturated ammonium chloride solution and extracted once with 200 ml of ethyl acetate and twice with 150 ml of ethyl acetate each time. The organic phases were washed with 100 ml of water, combined, dried with MgSO4 and filtered. The filtrate was concentrated and the residue, 23.4 g of brown oil, was chromatographed on 750 g of silica gel with hexane/ethyl acetate mixtures (4:1 to 2:1). 7.1 g (70%) of 3-(1,3-dioxolan-2-yl)-2-methylpropiophenone were isolated as a yellow oil.

1. temperatureagain cooled to -70° C.
2. stirringstirred for 15 minutes
3. customwas brought to room temperature
4. stirringstirred for 2 hours
5. extractionextracted once with 200 ml of ethyl acetate and twice with 150 ml of ethyl acetate each time
6. washThe organic phases were washed with 100 ml of water
7. dry with materialdried with MgSO4
8. filtrationfiltered
9. concentrationThe filtrate was concentrated
10. customthe residue, 23.4 g of brown oil, was chromatographed on 750 g of silica gel with hexane/ethyl acetate mixtures (4:1 to 2:1)

ORD record

ord-98b52b38bcc94eb9801a5890cfe7e21f

Source dataset

uspto-grants-1994_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05292732