Water → HCID 19832900, compound

To a stirred mixture of 28.1 g of pivaloyl chloride and 150 mL of trifluoroacetic acid, 18.01 g of dopamine hydrobromide were added. The mixture was stirred for 2 hours, then 14 mL of water were added and the mixture was concentrated in vacuo. The residual oil was dissolved in chloroform and washed with cold 10% KHCO3 solution until CO2 evolution ceased. The layers were separated and washed with water and the chloroform layer was dried over MgSO4, filtered and evaporated to dryness. The residue was taken up in 100 mL of ethyl acetate and 7 g of oxalic acid were added together with 100 mL of ethyl acetate. The resultant solution was filtered to remove insoluble materials and 1.6 g oxalic acid in 25 mL of ethyl acetate were added. The mixture was concentrated in vacuo and cooled. The crystals which formed were isolated by filtration, giving 13 g of the title compound. Cooling of the mother liquor afforded a second crop of crystals (5.9 g). The product had the formula: ##STR138##

1. additionwere added
2. concentrationthe mixture was concentrated in vacuo
3. dissolutionThe residual oil was dissolved in chloroform
4. washwashed with cold 10% KHCO3 solution until CO2 evolution
5. customThe layers were separated
6. washwashed with water
7. dry with materialthe chloroform layer was dried over MgSO4
8. filtrationfiltered
9. customevaporated to dryness
10. addition7 g of oxalic acid were added together with 100 mL of ethyl acetate
11. filtrationThe resultant solution was filtered
12. customto remove insoluble materials and 1.6 g oxalic acid in 25 mL of ethyl acetate
13. additionwere added
14. concentrationThe mixture was concentrated in vacuo
15. temperaturecooled
16. customThe crystals which formed
17. customwere isolated by filtration

ORD record

ord-cb23c94ab813446e8741b29ecebff4f3

Source dataset

uspto-grants-1991_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05017566