Reaction #570803

Reaction equation

5-(1,3-Dioxepan-2-yl)-2,3-pyridinedicarboxylic acid, dimethyl ester

2-amino-2,3-dimethylbutyramide

potassium tert-butoxide

→

title compound

Yield 57.2%

5-(1,3-Dioxepan-2-yl)-2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)nicotinic acid

Yield 57.2%

Solvents

toluene

toluene

water

water

Conditions

Workup

1. 1
   TemperatureThe mixture is heated for 3 hours from 60° to 70° C
2. 2
   Concentrationthe mixture is concentrated in vacuo
3. 3
   Otherto give an oil
4. 4
   Washwashed with ether
5. 5
   Extractionextracted with methylene chloride
6. 6
   DryingThe combined methylene chloride extracts are dried over anhydrous magnesium sulfate
7. 7
   Concentrationconcentrated in vacuo

Procedure

5-(1,3-Dioxepan-2-yl)-2,3-pyridinedicarboxylic acid, dimethyl ester (0.9 g, 0.00305 mol) in toluene is added to 2-amino-2,3-dimethylbutyramide (0.4 g, 0.00305 mol) and potassium tert-butoxide (0.69 g, 0.0061 mol) in toluene. The mixture is heated for 3 hours from 60° to 70° C. The reaction mixture is cooled to room temperature, water is added and the mixture is concentrated in vacuo to give an oil. The oil is diluted with water and washed with ether. The aqueous solution is acidified to pH 3.1 with 2 normal hydrochloric acid solution and extracted with methylene chloride. The combined methylene chloride extracts are dried over anhydrous magnesium sulfate and concentrated in vacuo to give the title compound as a white solid (0.63 g, 57%) mp 60°-69° C., identified by IR and NMR spectral analyses.

Source