Nitriles are useful functional groups in synthetic organic chemistry. The most common and well-known procedure for the preparation of nitriles is the nucleophilic displacement of substrates with suitable leaving groups such as halogen compounds, aryl sulfonates, alcohols, esters, ethers, nitro or amino compounds and diazonium salts with inorganic cyanide ions[1]. Nitriles are the key constituents of many naturally occurring compounds and also serve as an important synthetic intermediate for various agricultural chemicals, dyes, material sciences and as intermediates in microbial metabolism. Nitriles are important starting materials for the preparation of amines, amides, carboxylic acids, aldehydes, esters, and ketones. The classical methods for the preparation of nitriles include Kolbe nitrile synthesis[2], ammoxidation of aldehydes[3], Sandmeyer reaction of diazonium salts and hydrocyanation of alkenes. During the past decade, aldoximes have received more focus on preparation of nitriles from aldehydes and several methods are reported in literature. For example, aldehydes were transformed into nitriles by using Zn/I2 water and iodine in ionic liquid, NH4OAc under microwave irradiation, NH2OH.HCl under microwave irradiation, I2/NH3/THF catalyst, NaN3/AlCl3 catalyst, HY-zeolite catalyst under microwave irradiation and H2O2/NH2OH/Cu. Most of the existing methods suffer from one or more of the disadvantages such as limited substrate scope, high reaction temperatures, low yields, and use of excess and toxic reagents. Therefore,development of a mild, efficient, and versatile method is still strongly desirable. In this study, sulfamic acid was selected and conducted to find the advantage of it in the conversion of aldehydic compounds into nitrile-containing ones. We have chosen 4-chlorobenzaldehyde as our model compound for the desired transformation. Therefore, the reaction conditions were initially optimized using the mole-ratio of the catalyst, reaction time, temperature of the reaction, the kind of solvent for the model reaction. After the optimization, the treatment of various derivatives of aldehydic-containing compounds with hydroxylamine hydrochloride in the presence of catalytic amount of sulfamic acid as catalyst in refluxing CH3CN gave the corresponding nitrile compounds in good to excellent yields.(Scheme 1)

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