Boron trifluoride etherate → 1,1-Diethoxy-4,4-dimethoxypentan-3-one

Temperature

-78 °C

Boron trifluoride etherate (17.03 g, 120.0 mmol) was added dropwise over 15 min to a cooled (−40° C.) solution of triethyl orthoformate (14.82 g, 100.0 mmol) in dichloromethane (50 ml). Stirring was continued for 10 min then the solution was transferred to an ice-water bath and stirred at 0° C. for 20 min. The mixture was cooled to −78° C., and 3,3-dimethoxy-2-butanone (6.61 g, 50.0 mmol) added followed by dropwise addition of N,N-diisopropylethylamine (19.39 g, 150.0 mmol) over 15 min. Stirring was continued for 1 h then the solution was poured onto a vigorously stirred mixture of saturated sodium hydrogencarbonate solution (500 ml) and dichloromethane (200 ml). The organic phase was separated, washed with ice-cold 1M sulfuric acid solution (2×500 ml) and ice-cold water (2×500 ml), dried over anhydrous sodium sulfate solution and evaporated to give 1,1-diethoxy-4,4-dimethoxypentan-3-one (11.72 g, 100%) as an orange oil.

1. customthe solution was transferred to an ice-water bath
2. stirringstirred at 0° C. for 20 min
3. stirringStirring
4. waitwas continued for 1 h
5. customThe organic phase was separated
6. washwashed with ice-cold 1M sulfuric acid solution (2×500 ml) and ice-cold water (2×500 ml)
7. dry with materialdried over anhydrous sodium sulfate solution
8. customevaporated

ORD record

ord-316d640588be4ef782163ede87b24612

Source dataset

uspto-grants-2003_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06642229B2