Acetic Acid → HCID 21184385, compound

HRID 1385211Notes

Reaction equation

HRID 1385211 reaction equation
[O:1]=[C:2]1[C:11]2[N:12]=[C:13]([C:15]3[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=3)[S:14][C:10]=2[C:9](=[O:21])[C:8]2[C:7]([O:22]C)=[CH:6][CH:5]=[CH:4][C:3]1=2.C(O)(=O)C.Br>>[O:1]=[C:2]1[C:11]2[N:12]=[C:13]([C:15]3[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=3)[S:14][C:10]=2[C:9](=[O:21])[C:8]2[C:7]([OH:22])=[CH:6][CH:5]=[CH:4][C:3]1=2

Participants

4

Reactant 3

HCID 176Acetic AcidHCID 260Hydrogen BromideHCID 21184413HCID 21184413, compound

Product 1

HCID 21184385HCID 21184385, compoundYield 33%

Conditions

Temperature
10 °C

Procedure

A suspension of 1.00 g (0.003 mol) of 4,9-dihydro-4,9-dioxo-8-methoxy-2-phenyl-naphtho[2,3-d]-thiazole (Example 23) in 67 mL (1.160 mol) of acetic acid and 67 mL (0.570 mol) of hydrobromic acid is heated to reflux for 5 h 30 min. After cooling to 10° C., the reaction medium is filtered through fritted glass. The precipitate consists of 200 mL of chloroform. The organic phase is washed with a 3% ammonia solution (3×40 mL) and dried over calcium chloride. The yellow solid obtained after evaporation at reduced pressure of the solvent is purified on a medium-pressure column (support: silica 6-35 mm, eluant: toluene/dichloromethane, 100/0, 50/50, 0/100), then recrystallized 3 times in a toluene/heptane mixture, 50/50, to produce 0.302 g of 4,9-dihydro-4,9-dioxo-8-hydroxy-2-phenyl-naphtho[2,3-d]thiazole.

Workup

  1. temperatureis heated
  2. temperatureto reflux for 5 h 30 min
  3. filtrationthe reaction medium is filtered through fritted glass
  4. washThe organic phase is washed with a 3% ammonia solution (3×40 mL)
  5. dry with materialdried over calcium chloride
  6. customThe yellow solid obtained
  7. customafter evaporation at reduced pressure of the solvent
  8. customis purified on a medium-pressure column (support: silica 6-35 mm, eluant: toluene/dichloromethane, 100/0, 50/50, 0/100)
  9. customrecrystallized 3 times in a toluene/heptane mixture, 50/50

Sources & evidence

ORD record
ord-f766e45e07364e0983d49778258198c2
Source dataset
uspto-grants-2001_07
Patent number
US06262095B1

Reaction notes

Loading…