Hydrogen Bromide → HCID 19594652, compound

HRID 612584Notes

Reaction equation

HRID 612584 reaction equation
C[O:2][C:3]1[CH:15]=[CH:14][C:13]2[C:12]3[C:7](=[CH:8][CH:9]=[CH:10][C:11]=3[O:16]C)[C:6](=[O:18])[C:5]=2[CH:4]=1.C1(=O)C2C(C3C(C=2)=CC=CC=3)=CC=C1.Br>C(O)(=O)C.C(Cl)Cl>[OH:2][C:3]1[CH:15]=[CH:14][C:13]2[C:12]3[C:7](=[CH:8][CH:9]=[CH:10][C:11]=3[OH:16])[C:6](=[O:18])[C:5]=2[CH:4]=1

Participants

6

Reactant 3

HCID 260Hydrogen BromideHCID 848560HCID 848560, compoundHCID 22281833Fluoreneone

Product 1

HCID 19594652HCID 19594652, compound

Reagents, catalysts & solvents 2

HCID 176Acetic AcidSolventHCID 6344DichloromethaneSolvent

Conditions

Temperature
80 °C

Procedure

Prepare a solution of 2,5-dimethoxy-fluoren-9-one (7.5 g, 0.031 mmole) in 50 mL glacial acetic acid and warm to 80° C. Once all of the fluorenone goes into solution, add 150 mL hydrogen bromide (48% solution). Continue heating to reflux, redissolving any precipitate formed, and reflux overnight. Cool to room temperature and filter. Wash the filtrate with water. Take-up the solids in ethyl acetate and dissolve by heating in a steam bath. Filter through a short column of silica, eluting with hot ethyl acetate. Condense the ethyl acetate eluent on a rotary evaporatory to obtain a dark red solid. Heat in hot methylene chloride to dissolve undesired solid and filter to obtain 2,5-dihydroxy-fluoren-9-one. m.p. 298-301 dec. (Yield 9.4 g, 97%).

Workup

  1. temperatureContinue heating
  2. temperatureto reflux
  3. dissolutionredissolving any precipitate
  4. customformed
  5. temperaturereflux overnight
  6. temperatureCool to room temperature
  7. filtrationfilter
  8. washWash the filtrate with water
  9. dissolutiondissolve
  10. temperatureby heating in a steam bath
  11. filtrationFilter through a short column of silica
  12. washeluting with hot ethyl acetate
  13. customCondense the ethyl acetate eluent on a rotary evaporatory
  14. customto obtain a dark red solid
  15. dissolutionto dissolve undesired solid
  16. filtrationfilter

Sources & evidence

ORD record
ord-5e2a1ac631fa4b2cb05b6313f1d5e9f6
Source dataset
uspto-grants-1999_12
Patent number
US06004959

Reaction notes

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