Reaktion #2344933

Reaktionsgleichung

hydrochloric acid

Compound 63

6-Acetyl-3-[1-(6,7-dimethoxy-4-quinazolinyl)-4-piperidinyl]-1,2,3,4-tetrahydro-1-methyl-2,4-dioxo-quinazoline

hypobromous acid

sodium hydroxide

bromine

→

Compound 62

Ausbeute 21.3%

6-Carboxy-3-[1-(6,7-dimethoxy-4-quinazolinyl)-4-piperidinyl]-1,2,3,4-tetrahydro-1-methyl-2,4-dioxo-quinazoline

Ausbeute 21.3%

Lösungsmittel

1,4-dioxane

chloroform

1,4-dioxane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigewas prepared
2. 2
   Extraktionfollowed by extraction with chloroform
3. 3
   WaschenThe organic layer was washed
4. 4
   Sonstigedried
5. 5
   workup.DISTILLATIONthe solvent was distilled off under reduced pressure
6. 6
   workup.ADDITIONTo the residue was added ether
7. 7
   Filtrationthe precipitated crystals were collected by filtration
8. 8
   Sonstigedried

Vorschrift

In a solvent mixture of 30 ml of 1,4-dioxane and 5 ml of chloroform was suspended 245.0 mg (0.50 mmol) of Compound 63 obtained in Example 50. The suspension was added to a solution of hypobromous acid (3 mmol) which was prepared by adding 0.15 ml of bromine to a solvent mixture of 3 ml of a 2N aqueous solution of sodium hydroxide and 1 ml of 1,4-dioxane under ice cooling. The mixture was stirred at room temperature for one day, and then neutralized by addition of 4N hydrochloric acid, followed by extraction with chloroform. The organic layer was washed and dried, and the solvent was distilled off under reduced pressure. To the residue was added ether, and the precipitated crystals were collected by filtration and dried to give 52.4 mg (yield: 21%) of Compound 62 as white crystals.

Quelle