efficient buchwald hartwig reaction catalyzed by spions-bis(nhc)-pd(ii)

a powerful and convenient reaction procedure for the c-n coupling reaction (the buchwald-hartwig reaction), yielding products of n-arylanilines and n-arylamines in both conventional heating and microwave irradiation has been reported. the protocol utilizes a stable and new supper ferromagnetic nanoparticle chelating n-heterocyclic dicarbene palladium(ii) complex (pd-nhc) as catalyst which helps/allows us to complete the reaction with only 0.002 mol% pd producing high yield products. we also examined the reusability of the catalyst. it was found that the catalyst could be recovered by external magnetic field and  reused for seven times without obvious loss in catalytic activity.