Adamantanone → Idramantone

Adamantanone (12 g, 80 mmol) was added under stirring to nitric acid (98%, 100 mL) at ice bath temperature over a period of 15 minutes. The reaction mixture was stirred at room temperature for 72 h and then heated to 60° C., for 2 h until most of the nitrogen dioxide evaporated. Excess nitric acid was distilled off under reduced pressure. The light yellow oil solidified upon cooling (NO3 adduct of the hydroxyketone). Water (40 mL) and conc. H2SO4 (98%, 15 mL) were added. The resulting clear yellow solution was heated on the steam bath in a hood (nitrous fumes) for 1 h. The solution was then cooled and extracted with a 2:1 mixture of n-hexane and diethylether to remove unreacted adamantanone (1.0 g). The acid layer was neutralized with 30% aq. NaOH solution, and while warm, extracted with chloroform. The extracts were combined, washed with brine solution, and concentrated in vacuum. The crude product was dissolved in CH2Cl2 (15 mL) and hexane was added until no more precipitate was formed. The solid material was isolated by filtration and dried to get 5-hydroxy-adamantan-2-one. Yield: 9.0 g (70%). Solid; M.R: 278.8-300° C. (decomposes) m/z (M+1) 167; 1H NMR (CDCl3) 300 MHz δ 2.70-2.55 (m, 2H), 2.36-2.32 (m, 1H), 2.11-1.93 (m, 10H). 13C NMR (CDCl3) 75 MHz δ 217.0, 66.7, 46.7, 46.6, 44.7 (2C), 43.8, 37.9 (2C), 29.5.

1. customevaporated
2. distillationExcess nitric acid was distilled off under reduced pressure
3. temperatureupon cooling (NO3 adduct of the hydroxyketone)
4. additionWater (40 mL) and conc. H2SO4 (98%, 15 mL) were added
5. temperatureThe resulting clear yellow solution was heated on the steam bath in a hood (nitrous fumes) for 1 h
6. temperatureThe solution was then cooled
7. extractionextracted with a 2:1 mixture of n-hexane and diethylether
8. customto remove unreacted adamantanone (1.0 g)
9. temperaturewhile warm
10. extractionextracted with chloroform
11. washwashed with brine solution
12. concentrationconcentrated in vacuum
13. dissolutionThe crude product was dissolved in CH2Cl2 (15 mL)
14. additionhexane was added until no more precipitate
15. customwas formed
16. customThe solid material was isolated by filtration
17. customdried

ORD record

ord-fdab54e633da4af5a22a4506d4e019e2

Source dataset

uspto-grants-2011_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07985759B2