Reaction #55455

Reaction equation

2-(1-benzyl-5-methyl-4-imidazolyl)-4-carbethoxy-1,3-dithian-5-one

sulfuric acid

→

2-(1-benzyl-5-methyl-4-imidazolyl)-1,3-dithian-5-one

Solvents

hydrochloric acid

water

Conditions

Workup

1. 1
   TemperatureThe mixture is cooled
2. 2
   Washwashed with diethyl ether
3. 3
   Filtrationfiltered through a charcoal pad
4. 4
   Extractionextracted into methylene chloride
5. 5
   OtherThe solvent is dried
6. 6
   Otherevaporated

Procedure

A mixture of 2-(1-benzyl-5-methyl-4-imidazolyl)-4-carbethoxy-1,3-dithian-5-one (15.5 g., 0.041 mole) in water (40 ml.) containing concentrated sulfuric acid (3.0 ml.) is heated at 100° C. for 4-5 hours. The mixture is cooled, diluted with 10% hydrochloric acid, washed with diethyl ether and filtered through a charcoal pad. The filtrate is made basic with sodium carbonate solution and extracted into methylene chloride. The solvent is dried and evaporated to give a dark brown oil (11.2 g.), 2-(1-benzyl-5-methyl-4-imidazolyl)-1,3-dithian-5-one, which is used as is in subsequent steps.

Source