Hexanoyl chloride → 4-Hexanoylamino-isophthalic acid

HRID 1413810Notes

Reaction equation

HRID 1413810 reaction equation
C[O:2][C:3](=[O:15])[C:4]1[CH:13]=[CH:12][C:11]([NH2:14])=[C:6]([C:7]([O:9]C)=[O:8])[CH:5]=1.[C:16](Cl)(=[O:22])[CH2:17][CH2:18][CH2:19][CH2:20][CH3:21]>O1CCOCC1.N1C=CC=CC=1>[C:16]([NH:14][C:11]1[CH:12]=[CH:13][C:4]([C:3]([OH:2])=[O:15])=[CH:5][C:6]=1[C:7]([OH:9])=[O:8])(=[O:22])[CH2:17][CH2:18][CH2:19][CH2:20][CH3:21]

Participants

5

Reactant 2

HCID 67340Hexanoyl chlorideHCID 11095854Dimethyl 4-aminoisophthalate

Product 1

HCID 202907704-Hexanoylamino-isophthalic acidYield 94.9%

Reagents, catalysts & solvents 2

HCID 1049PyridineSolventHCID 312751,4-DioxaneSolvent

Procedure

Dimethyl-4-amino-isophthalate (9 g) in 60 ml of dioxane and 18 ml of pyridine is treated with hexanoyl chloride (8.8 g) at room temperature for 16 hours. After dilution with water and extraction with ethyl acetate, the solution is washed with 40% citric acid and 5% NaHCO3 and evaporated to dryness, so obtaining dimethyl-4-hexanoylamino-isophthalate (14.8 g) that is dissolved in 75 ml of dioxane and treated with 75 ml of 2 N NaOH at room temperature for 6 hours. After acidification with HCl the precipitate is collected under vacuum and washed until neutral. 4-hexanoylamino-isophthalic acid (11.4 g) is obtained, which is treated with 26 ml of acetic anhydride at reflux for 10'. After cooling, dilute with 30 ml of isopropyl ether and filter. 6-carboxy-2-pentyl-4H-3,1-benzoxazin-4-one (7.3 g; m.p. 185°-190° C.) is obtained, which is treated at room temperature first with 70 ml of 32% ammonium hydroxide for 16 hours and then with 50 ml of 2 N NaOH for 2 hours. After acidification with 2 N HCl, the precipitate is filtered off and crystallized from ethanol, so obtaining 6-carboxy-2-pentyl-3,4-dihydro-4-oxo-quinazoline (6.1 g; m.p. 311°-313° C.).

Workup

  1. extractionAfter dilution with water and extraction with ethyl acetate
  2. washthe solution is washed with 40% citric acid and 5% NaHCO3
  3. customevaporated to dryness, so obtaining dimethyl-4-hexanoylamino-isophthalate (14.8 g) that
  4. dissolutionis dissolved in 75 ml of dioxane
  5. additiontreated with 75 ml of 2 N NaOH at room temperature for 6 hours
  6. customAfter acidification with HCl the precipitate is collected under vacuum
  7. washwashed until neutral

Sources & evidence

ORD record
ord-9a491c7e7b684fc98e585ef861c5fe58
Source dataset
uspto-grants-1981_02
Patent number
US04251531

Reaction notes

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