Genesis of thiacalixarenes: a one-pot highly efficient synthesis of TC4A

This Letter reports the results of our studies towards the synthesis of thiacalixarenes. In an effort to develop an efficient and inexpensive synthetic methodology for thiacalixarenes, several trials were conducted to study the effect of base/template, solvents, catalyst, phenol substitutions and temperature profile. Microwave synthesis was also tested to reduce the overall time for the reaction. Based on the results of these investigations, a detailed reaction mechanism is proposed and an optimized synthetic procedure for p-tert-butylthiacalix[4]arene is demonstrated.