Chloromethyl Methyl Ether → Methyl 3-methoxy-2,2-dimethylpropanoate

Temperature

-78 °C

To a solution of diisopropylamine (8.71 g, 86.1 mmol) in anhydrous THF (130 ml) was added under argon atmosphere a solution of n-butyl lithium in hexane (1.62N, 53.1 ml, 86.1 mmol) at -20° C. The reaction mixture was stirred for 30 min. and cooled to -78° C. To the reaction mixture were added a solution of methyl isobutyrate (8.00 g, 78.3 mmol) in 15 ml of anhydrous THF and HMPA (14.0 g, 78.3 mmol), and the mixture was stirred for one hour at -78° C. To this was added a solution of chloromethyl methyl ether (7.57 g, 94.0 mmol) in 15 ml of anhydrous THF, and the reaction mixture was stirred for 2 hrs. at -78° C. To an aqueous saturated solution of ammonium chloride (300 ml) were added the above solution and water (100 ml). The resulting mixture was extracted with ether (400 ml). The aqueous layer was reextracted with ether (200 ml×2). The combined ether layers were washed with water (300 ml) and with brine, and dried over anhydrous magnesium sulfate. Ether was distilled out at normal pressure and the residue was distilled (b.p. 98°-99° C./107 mmHg) to give methyl 2,2-dimethyl-4-oxapentanoate (8.38 g, 57.4 mmol, 73.3%) as an oily material. The product was assigned the structure by the following data.

1. stirringthe mixture was stirred for one hour at -78° C
2. stirringthe reaction mixture was stirred for 2 hrs
3. customat -78° C
4. extractionThe resulting mixture was extracted with ether (400 ml)
5. washThe combined ether layers were washed with water (300 ml) and with brine
6. dry with materialdried over anhydrous magnesium sulfate
7. distillationEther was distilled out at normal pressure
8. distillationthe residue was distilled (b.p. 98°-99° C./107 mmHg)

ORD record

ord-0dcfc6da051548589b1805dfe0cb69cd

Source dataset

uspto-grants-1988_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04775692