Microwave-enhanced cyanation of aryl halides with a dimeric ortho-palladated complex catalyst

Abstract

A new dimeric ortho-palladated complex of 2-methoxyphenethylamine was synthesized and characterized and its application as a cyanation catalyst was investigated. The main advantages of this catalyst are its easy preparation, handling, stability, and moisture insensitivity. Thus, [Pd{C 6 H 3 (CH 2 CH 2 NH 2 )-4-OMe-5-j 2 -C,N}(l-Br)] 2 showed excellent catalytic activity for the cyanation of aryl iodides and bromides with K 4 [Fe(CN) 6 ], in DMF in the presence of K 2 CO 3 under microwave irradiation and conventional heating at 130°C to give the desired cyanoarene products in good to high yields. The less reactive aryl chlorides also react with K 4 [Fe(CN) 6 ] to give moderate yields of the aromatic nitriles. The effects of various parameters such as solvent, base, and amount of catalyst were studied. The reaction is suitable for a wide variety of substituted aryl halides with different electronic properties. Application of microwave irradiation improved the yields of the reactions and reduced the reaction times from hours to minutes.

CN Bond Formation Using Highly Effective and Reusable Nickel Ferrite Nanoparticles in Water

“…[30,31] These bimetallic compounds that crystallize in the spinel form show superparamagnetic properties originating from the moment of antiparallel spines between ferric ions at tetrahedral sites and nickel ions at octahedral sites. [30,31] In continuation of our previous work, [32][33][34][35][36] we reported the use of a new heterogeneous nickel ferrite nanocatalyst with high efficiency for the CÀN cross-coupling reaction. The presented catalyst system was active and showed good generality in the reaction of various types of aryl halides and different amines or amides such that both aliphatic and aromatic amines and both cyclic and acyclic primary and secondary amines could be coupled with a wide range of aryl halides containing both electron-donating and electron-withdrawing substituents under these reaction conditions.…”

Fabrication of Pd Nanoparticles Embedded C@Fe3O4 Core–Shell Hybrid Nanospheres: An Efficient Catalyst for Cyanation in Aryl Halides

“…29,34 In the first step, oxidative addition of aryl halides to Pd(0) leads to a Pd(II) species (A). In the second step, ligand exchange from the inner coordination sphere of 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 22 leaching, however hryl halides also contributed to a lesser degree.…”

“…Since then a number of reports were available using this reagent in the presence of Pd catalysts such as Pd(OAc) 2 , 30-31 several Pd complexes [32][33][34][35][36][37][38][39][40][41][42][43][44][45] and Pd/C, [46][47] were developed. The serious drawbacks of these metal catalysts are metal contaminations in the final products, non-reusability and deactivation of the catalysts associated with the use of homogeneous system and hence are still unwelcoming.…”

Synthesis of tertiary aryl amines of various aryl halides and secondary amines using ortho‐palladated complex of tribenzylamine

“…In continuation of our recent investigations on the synthesis and applications of palladacycle catalysts in cross‐coupling reactions, we now report the extension of dimeric [Pd{C6H 4 (CH 2 N(CH 2 Ph) 2 )} (μ‐Br)] 2 homogeneous complex as a thermally stable and oxygen‐insensitive catalyst in the C―N cross‐coupling reaction. In this paper, the efficiency of this dimeric complex of palladium and tribenzylamine was investigated in an amination reaction with various aryl halides and secondary amines (Scheme ).…”