Active-copper-promoted mild and expeditious N-arylations of amines, amides, imides, and b-lactams with aryl halides under microwave irradiation conditions are reported. These reactions can be performed at 85-90 °C in aqueous media as well as under solvent-free conditions to give good yields. However, under solvent-free conditions, lower yields are obtained.Aryl-nitrogen bonds are prevalent in many compounds that are of academic, pharmaceutical, and industrial interest. Transition-metal-mediated C-N bond-forming processes are important fundamental transformations and are extensively utilized for N-arylations. The Ullmann condensation has been a powerful method for the coupling of aryl halides with amines. 1-3 Typically, Ullmann coupling protocols necessitate the use of copper metal or copper salts, base, and high reactions temperatures. Recently, the palladium-catalyzed aryl amination has received attention as a synthetically useful method due to the lower temperature required. [4][5][6] In the b-lactam field, the Ullmann-type condensation under basic conditions leads to decomposition of the starting material instead of the expected formation of penem and cephem analogues. 7-10 In about 100 years of study of Ullmann-type condensations, there have been only limited examples where no base is used and the copper metal or copper salt catalyst itself acts as the acceptor of halogen. 9-12 However, all of these reactions suffer from one or more disadvantages such as higher reaction temperatures, longer reaction times, and lower yields.Microwave (MW) irradiation has now gained popularity as a powerful tool for rapid and efficient synthesis of a variety of organic compounds in various solvents as well as solvent-free conditions. 13-16 The application of MW irradiation to provide enhanced reaction rates and improved product yields in chemical synthesis has been extended to modern drug discovery processes, 17,18 and it is proving quite successful in the formation of carbon-heteroatom and carbon-carbon bonds. 19,20 Water is the cheapest, safest, and most non-toxic solvent in the world. It is a good absorber of microwave energy 21,22 and has been successfully employed as solvent for various organic syntheses. 23-27 Utilization of water as an eco-friendly reaction medium in conjunction with MW irradiation is gaining widespread acceptance. [28][29][30][31][32] Considering the above valid points and in pursuing our work on the development of green synthetic processes, 33-36 we have devised active-copper-promoted mild and expeditious N-arylations with aryl halides under MW irradiation. These reactions can be preformed at 85-90 °C in aqueous media as well as under solvent-free conditions. However, the yields are lower under solvent-free conditions, especially in the case of b-lactam derivatives (Tables 1 and 2).The present method in its entirety involves intermittent irradiation of an intimate mixture of an aryl halide, a R 2 NH compound (an amine, amide, imide or b-lactam), and active copper 37 in neat conditions or their aqueous ...

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S O Ph Me O Ar 1 CHO N S S O Ar O O HS Ar 1 S N S Ar r.t., 76-90% Pro 2 SO 4 88-95% eeA low hazardous, one-pot, expeditious annulation involving tandem Knoevenagel, Michael and ring transformation reactions of 3-arylrhodanines, aromatic aldehydes and a mercaptoacetyl transfer agent, 2methyl-2-phenyl-1,3-oxathiolan-5-one, diastereoselectively yields 6-mercaptopyranothiazoles. The annulation is performed using a chiral ionic liquid (Pro 2 SO 4 ) as the reaction medium and catalyst, and proceeds via an isolable intermediate.