Pd(0)-S-methylisothiourea grafted onto mesoporous MCM-41 and its application as heterogeneous and reusable nanocatalyst for the Suzuki, Stille and Heck cross coupling reactions

Abstract

In this project palladium (0) S-methylisothiourea was grafted into MCM-41 mesoporous silica. Palladium (0) S-methylisothiourea complex supported on MCM-41 (Pd(0)-SMT-MCM-41), as heterogeneous and reusable catalyst, was used in C–C bond formation between various aryl halides with sodium tetraphenylborate or phenylboronic acid (Suzuki reaction), aryl halides with triphenyltin chloride (Stille reaction), and aryl halides with styrene or n-butyl acrylate (Heck reaction). This catalyst was characterized by various physico-chemical techniques such as X-ray diffraction, transmission electron microscopy, scanning electron microscopy (SEM/EDX), thermal gravimetric analysis (TGA/DTA), fourier transform infrared spectroscopy and inductively coupled plasma. The results indicated that Pd(0)-SMT-MCM-41 catalyst could be easily recovered from reaction mixture for several consequence runs without significant loss of its catalytic activities.