Pyridine → HCID 178461647, compound

Temperature

25 °C

32.7 g (about 111 mmol) of crude (R,R)-1,1'-bis(1-hydroxyethyl)ferrocene were dissolved in 30 ml of pyridine and admixed with 30 ml of acetic anhydride. After stirring for 16 hours at 25° C., the excess anhydride was hydrolysed with 200 ml of ice water and the mixture was extracted three times with 100 ml each Time of diethyl ether. The combined organic phases were washed once more with about 150 ml of water, dried over magnesium sulphate and evaporated. The residue was admixed with 200 ml of hexane and the solvent was removed on a rotary evaporator (<40° C). This procedure was repeated two more times. The resulting dark brown oil was dissolved in 200 ml of isopropyl alcohol and admixed with 120 ml of dimethylamine (50% in water). After stirring at 25° C. (16 hours), 200 ml of water were added and the pH of the reaction mixture was adjusted to 1 using 100 ml of 32% strength HCl and the aqueous phase was washed twice with 100 ml each time of diethyl ether. The aqueous phase was basified with sodium hydroxide solution (40% strength) to a pH of 12-14 and extracted three times with 100 ml each time of diethyl ether. The combined organic phases were dried over magnesium sulphate and evaporated. In order to remove isopropyl alcohol still present, the oil obtained was admixed with about 100 ml of hexane and again evaporated on a rotary evaporator. This procedure was repeated two more times. Drying in a high vacuum gave 24.1 g (66%, based on 1,1'-diacetylferrocene) of the title compound in the form of a dark brown oil. (Without hydrochloric acid treatment, the yield rises to 86%).

1. extractionthe mixture was extracted three times with 100 ml each Time of diethyl ether
2. washThe combined organic phases were washed once more with about 150 ml of water
3. dry with materialdried over magnesium sulphate
4. customevaporated
5. customthe solvent was removed on a rotary evaporator (<40° C)
6. dissolutionThe resulting dark brown oil was dissolved in 200 ml of isopropyl alcohol
7. stirringAfter stirring at 25° C. (16 hours), 200 ml of water
8. additionwere added
9. washthe aqueous phase was washed twice with 100 ml each time of diethyl ether
10. extractionextracted three times with 100 ml each time of diethyl ether
11. dry with materialThe combined organic phases were dried over magnesium sulphate
12. customevaporated
13. customIn order to remove isopropyl alcohol still present
14. customthe oil obtained
15. customagain evaporated on a rotary evaporator
16. customDrying in a high vacuum

ORD record

ord-dbdd013fa6384f5588254985eca391bb

Source dataset

uspto-grants-1998_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05760264