Self-assembled NiO–ZrO2nanocrystals with mesoscopic void space: An efficient and green catalyst for C–S cross-coupling reaction in water

Abstract

New NiO–ZrO₂ nanocrystals (MNZ-1) with mesoscopic self-assembly have been synthesized by using a non-ionic surfactant as the structure directing agent (SDA) via evaporation induced self-assembly (EISA) method. Powder X-ray diffraction (PXRD), N₂ sorption study and transmission electron microscopic (TEM) image analyses revealed the cubic structure, mesoporosity and mesoscopic self-assembly of ca. 7.0 nm sized tiny nanocrystals in the material. MNZ-1 catalyzes the aerobic aryl–sulfur cross-coupling reactions for a series of aryl-iodides with 4-chlorothiophenol in environment friendly water medium at elevated as well as room temperature. Pure ZrO₂ mesoporous nanocrystals are inactive, whereas pure NiO nanocrystals showed much lower catalytic activity under similar reaction conditions. The MNZ-1 nanocatalyst is completely non-air sensitive, inexpensive and effective for the synthesis of a series of essential biomolecules derived from diaryl sulfides.