2-Methoxyisobutylisonitrile (MIBI) is a key starting material in the preparation of technetium-99m hexakis (2-methoxyisobutylisonitrile). This cationic complex has been reported to be clinically useful as myocardial perfusion agent. In this work, we designed an improved synthetic method to prepare 2-methoxyisobutylisonitrile in a two step synthesis with an overall yield of 52.9 % , on the basis of 2-methoxyisobutylamine is a primary amine which, when is heated with a mixture of chloroform and alcoholic potash, produces an isonitrile. Its spectroscopic properties as well as the preparation of its copper and technetium-99m complexes are also presented. (Author).