“…Various methods are present for Heck reaction with several metalâmetal complexes and ligands like palladium complex of PdCl 2 (bipy), palladium Nâheterocyclic bisâcarbene (PdâNHDC) moiety containing a UiOâ67 type MOF (UiOâ67âPdâNHDC) catalyst, cellulose supported poly(hydroxamic acid) Pd(II) complex, complex of PdCl 2 with a multidentate cryptand ligand (Kryptofix 5), triphenylphosphine and tris(2âfuryl)phosphine with fluorinated palladium sources, tridentate SCS palladium(II) complexes, palladacycles, oximecarbapalladacycle, Pd/C in ionic liquid, N,Nâdimethylâ ÎČ âalanine with Pd(OAc) 2 , Nâphenylurea with Pd(OAc) 2 , silicaâsupported palladium catalyst, Pd(quinolineâ8âcarboxylate) 2 , pyrazolylâfunctionalized carbene palladium complexes, Pd anchored on Lâprolineâfunctionalized silica gel as catalyst, 2âaminophenyl diphenylphosphinite with Pd(OAc) 2 , trans â[PdCl 2 (DEA) 2 ], thiadiazolidine1âoxide with Pd 2 (dba) 3 , 2,2âdiaminoâ6,6âdimethylbiphenyl with Pd(OAc) 2 , cationic 2,2ââbipyridyl ligand, amino oxazoline ligands with Pd(OAc) 2 , Pd(LâProline) 2 , complexes of Pd and Cu with 2â(2ââhydroxyphenyl)â5,6âdihydroâ1,3âoxazine, Pd 2 (dba) 3 with methyl 4,6â O âbenzylideneâ3âdeoxyâ3â(diphenylphosphino)âαâDâaltropyranoside, InCl 3 , tridentate Schiff base palladium(II) complex, imidazolium ionic liquidâtagged Schiff base palladium complex, Pd(OAc) 2 with N â(1âmethylpyridinâ4(1 H )âylidene)amine ligands, and several catalysts systems without ligand…”