Réaction #3202

Équation de réaction

methyl 2-amino-6-methylbenzoate

dimethyl acetylenedicarboxylate

potassium t-butoxide

→

title compound

Rendement 66.4%

Dimethyl 4-hydroxy-5-methylquinoline-2,3-dicarboxylate

Rendement 66.4%

Solvants

t-butanol

Conditions de réaction

Traitement

1. 1
   Températurewas refluxed fpr 18 hr under a nitrogen atmosphere
2. 2
   Autreformed
3. 3
   TempératureAfter refluxing this mixture for 1.5 hr
4. 4
   Températureit was cooled to room temperature
5. 5
   Filtrationfiltered
6. 6
   Autreto separate the solids
7. 7
   workup.DISSOLUTIONThe solids were dissolved in water
8. 8
   Autreto form a precipitate
9. 9
   FiltrationThe mixture was filtered
10. 10
    Lavagethe collected solids were washed with water
11. 11
    Autredried

Mode opératoire

A stirred mixture of methyl 2-amino-6-methylbenzoate (1.50 g, 9.08 mM) and dimethyl acetylenedicarboxylate (1.40 g, 9.82 mM) in t-butanol (20 mL) was refluxed fpr 18 hr under a nitrogen atmosphere. The reaction mixture was cooled to room temperature and potassium t-butoxide (1.10 g, 9.82 mM) was added in one portion whereupon a precipitate formed. After refluxing this mixture for 1.5 hr, it was cooled to room temperature and filtered to separate the solids. The solids were dissolved in water and the resulting solution acidified with 1N H2SO4 to form a precipitate. The mixture was filtered and the collected solids were washed with water and dried to give the title compound (1.66 g, 66.4%) as a tan solid. An analytical sample of this material was obtained by recrystallization of a portion from ethyl acetate/hexane to give off white crystals, mp 167°-168° C.; MS(CI): 276 (M+H).

Source