Reaction #63239

Reaction equation

HCl

3-bromo-4-methoxy-2-(1-methylethoxy)benzoic acid

1,1'-carbonyldiimidazole

triethylamine

5-aminotetrazole

CaCl2

→

N-1H-tetrazol-5-ylbenzamide

Solvents

acetonitrile

Conditions

Workup

1. 1
   Temperatureis warmed
2. 2
   Temperatureat reflux under nitrogen atmosphere
3. 3
   TemperatureThe resulting mixture is warmed
4. 4
   Temperatureat reflux for 30 hours
5. 5
   Filtrationfiltered

Procedure

A mixture of 1.28 g (4.43 mmol) 3-bromo-4-methoxy-2-(1-methylethoxy)benzoic acid (prepared in Step 3) and 0.83 g 5.12 g (5.12 mmol) of 1,1'-carbonyldiimidazole in 15 ml of acetonitrile is warmed at reflux under nitrogen atmosphere (or CaCl2 filled drying tube) for one hour. The reaction mixture is treated with 1.07 g (10.62 mmol) of triethylamine and 0.44 g (5.17 mmol) of anhydrous 5-aminotetrazole. The resulting mixture is warmed at reflux for 30 hours. The reaction mixture is then poured onto 180 g of ice water and acidified with aqueous 10% HCl and filtered to give 1.32 g (1.58 theor., 84%) of 3-bromo-4-methoxy-2- 1-methylethoxy)-N-1H-tetrazol-5-ylbenzamide as a white solid having melting point 255°-256° C.

Source