Aerobic Cu and amine free Sonogashira and Stille couplings of aryl bromides/chlorides with a magnetically recoverable Fe3O4@SiO2 immobilized Pd(II)-thioether containing NHC.

• A magnetically recoverable heterogeneous catalyst Fe 3 O 4 @SiO 2 @NHC^SPh-Pd(II). • Fe 3 O 4 @SiO 2 @NHC^SPh-Pd(II) catalyzed cross couplings reactions at mild conditions. • Cu and amine free Sonogashira cross coupling of aryl/heteroarylbromides and acetylenes. • Fe 3 O 4 @SiO 2 @NHC^SPh-Pd(II) catalyzed Stille coupling of arylbromides/chlorides and trialkylstannanes. Two value added C C cross coupling reactions; Sonogashira and Stille couplings were achieved at milder conditions in the catalytic presence of a magnetically recoverable heterogeneous catalyst Fe 3 O 4 @SiO 2 @NHC^SPh-Pd(II). The catalyst was earlier reported for Suzuki-Miyaura reaction, and as an extension of its catalytic efficiency, the Stille and Sonogashira cross coupling reactions under aerobic condition has been explored in present report. The Sonogashira coupling of aryl bromides and terminal alkynes produced an excellent yield (~96% at 0.25 mol% Pd) of the desired coupling product under copper and amines free conditions. Moreover, an excellent Stille coupling of readily available and more latent aryl chlorides and trialkylstannane was obtained (yields up to 95% at 0.25 mol% Pd) in absence of toxic fluorides additives. The broad substrate scope of the catalyst for both the coupling reactions and the magnetically recoverable feature of catalyst make this reaction highly desirable for industrial applications of present heterogeneous catalysis. [ABSTRACT FROM AUTHOR]