Theoretical analysis of thermal isomerisation barrier of isocyanides into cyanides : A semiempirical approach

Department of Chemistry, Agrawal Post Graduate College, Jaipur, Rajasthan, India E-mail : jkjain8962@yahoo.co.in Department of Chemistry, University of Rajasthan, Jaipur-302 004, Rajasthan, India Manuscript received 25 June 2010, revised 18 May 2011, accepted 25 May 2011 AM1 semiempirical calculations for reactions have been performed and the effect of different substituents on thermal isomerisation barrier has been studied. As AM1 semiempirical calculations need much less time as compared to ab initio calculations, they have been employed to study the thermal rearrangement of five aliphatic and seven aromatic isocyanide→ cyanides. Variation in activation energy of isocyanide→ cyanides has been explained on the basis of electron releasing or electron withdrawing effect of different substituent, present in the molecule