Formic Acid → Methyl 4-oxoadamantane-1-carboxylate

Temperature

60 °C

A solution of 5-hydroxy-2-adamantanone (2.0 g, 12.0 mmol) in 99% formic acid (12 mL) was added dropwise with vigorous gas evolution over 40 minutes to a rapidly stirred 30% oleum solution (48 mL) heated to 60° C. (W. J. le Noble, S. Srivastava, C. K. Cheung, J. Org. Chem. 1983, 48, 1099-1101.). Upon completion of addition, more 99% formic acid (12 mL) was slowly added over the next 40 minutes. The mixture was stirred another 60 minutes at 60° C. and then slowly poured into vigorously stirred methanol (100 mL) cooled to 0° C. The mixture was allowed to slowly warm to 23° C. while stirring for 2 hours and then concentrated in vacuo. The residue was poured onto ice (30 g), and methylene chloride (100 mL) was added. The layers were separated, and the aqueous phase was extracted twice more with methylene chloride (100 mL aliquots). The combined methylene chloride solutions were concentrated in vacuo to 50 mL, washed with brine, dried over N2SO4, filtered, and concentrated in vacuo to provide the title compound as a pale yellow solid (2.5 g, 99% crude).

1. additionwas slowly added over the next 40 minutes
2. temperaturecooled to 0° C
3. temperatureto slowly warm to 23° C.
4. stirringwhile stirring for 2 hours
5. concentrationconcentrated in vacuo
6. additionThe residue was poured onto ice (30 g), and methylene chloride (100 mL)
7. additionwas added
8. customThe layers were separated
9. extractionthe aqueous phase was extracted twice more with methylene chloride (100 mL aliquots)
10. concentrationThe combined methylene chloride solutions were concentrated in vacuo to 50 mL
11. washwashed with brine
12. customdried over N2SO4
13. filtrationfiltered
14. concentrationconcentrated in vacuo

ORD record

ord-a9d49f7a5a32405f927671d261f3d4ad

Source dataset

uspto-grants-2007_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07238724B2