A practical and convenient method for the synthesis of anesthetic drug thiopental: using thiourea and sodium ethoxide

A general, simple, practical and convenient method has been described for the synthesis of anesthetic drug thiopental using thiourea in the presence of sodium ethoxide. Anesthetic drug of thiopental was prepared in two stages; during the first stage, the alkylation of mthyl cyanoacetate was performed which was then to be followed by cyclization. Alkylation of methyl cyanoacetate which was performed by 2-iodopentane in the presence of sodium ethoxide reacts with thiourea and then the process was followed by thiopental prepration in excellent yield. Some important aspects of this methodology are the high reactivity of the substrates, avoidance of the use of hazardous solvents, simplicity of the product separation, low cost of the substrates and reagents and high yield of product. This is a applicable and efficient method for the preparation of thiopental anesthesia in high yield and in an appropriate time.