p-Toluidine → 6-Oxoheptanoic acid

Temperature

0 °C

δ-Acetyl-n-valeric acid (1.0 g, 6.9 mmol) was dissolved in 50 ml anhydrous tetrahydrofuran and the solution cooled to 0° C. in an ice bath. N-methyl morpholine (0.76 ml, 6.9 mmol) was added followed by isobutyl chloroformate (0.90 ml, 6.9 mmol). After allowing the reaction to stir for 10 min, p-toluidine (0.74 g, 6.9 mmol) was added and the mixture stirred overnight at room temperature. The solvent was evaporated under reduced pressure and the residue redissolved in 150 ml ethyl acetate and 50 ml water. The organic phase was separated and extracted three times with 50 ml 0.1N hydrochloric acid, three times with 0.1N sodium hydroxide, twice with 50 ml brine and dried over sodium sulfate. After filtration from the drying agent and evaporation of the filtrate, the pale yellow solid was crystallized from ethyl acetate/hexanes yielding 1.2 g of needles that were homogeneous by thin layer chromatography (60:40 ethyl acetate/hexanes, Rf =0.31) m.p. 108.5°- 110° C.

1. customthe reaction
2. stirringthe mixture stirred overnight at room temperature
3. customThe solvent was evaporated under reduced pressure
4. dissolutionthe residue redissolved in 150 ml ethyl acetate
5. customThe organic phase was separated
6. extractionextracted three times with 50 ml 0.1N hydrochloric acid, three times with 0.1N sodium hydroxide
7. dry with materialtwice with 50 ml brine and dried over sodium sulfate
8. filtrationAfter filtration
9. customfrom the drying agent and evaporation of the filtrate
10. customthe pale yellow solid was crystallized from ethyl acetate/hexanes yielding 1.2 g of needles that

ORD record

ord-4b43802a1cf94deab1192543b8dc95b3

Source dataset

uspto-grants-1989_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04837305