2(1H)-Pyrimidinone, tetrahydro-1,3-dimethyl- → 2-(2,2-dimethoxy-1-ethyl)-5-methoxy-1-tetralone N,N-dimethylhydrazone

3.12 g of 5-methoxy-1-tetralone N,N-dimethylhydrazone and 4.15 ml of DMPU were dissolved in 70 ml of absolute THF under argon and cooled to -75°. 10.7 ml of a 1.6M solution of n-butyllithium in hexane were added dropwise. The mixture was stirred at -75° for 1 hour and thereupon treated slowly with 2.0 ml of bromoacetaldehyde dimethyl acetal. The mixture was left to warm to room temperature and stirred for 26 hours. 20 ml of water were added at about 0° and the mixture was extracted three times with ethyl acetate. After drying over sodium sulfate, the mixture was filtered, evaporated and the residue was chromatographed on silica gel with toluene, then with toluene/ethyl acetate 9:1. 1.62 g (37%) of 2-(2,2-dimethoxy-1-ethyl)-5-methoxy-1-tetralone N,N-dimethylhydrazone were obtained as an oil.

1. temperaturecooled to -75°
2. waitThe mixture was left
3. stirringstirred for 26 hours
4. extractionthe mixture was extracted three times with ethyl acetate
5. dry with materialAfter drying over sodium sulfate
6. filtrationthe mixture was filtered
7. customevaporated
8. customthe residue was chromatographed on silica gel with toluene

ORD record

ord-f0ae9af437a8485ebac27d545625552a

Source dataset

uspto-grants-1997_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05646173