Written by William Sommer, Ph.D

The aminocarbonylation of aryl halides has been an ongoing endeavor for the past 30 years. Since the first report of this reaction by Heck in the mid 70's, a plethora of metal catalyst were investigated to improve the yields and feasibility of this reaction. Working toward simplifying this transformation, Ju et al. report the first nickel phosphite catalytic system for the aminocarbonylation of different aryl iodides and bromides. Using Ni(OAc)₂ 4H₂O with tris(2,4-di-tert-butylphenyl) phosphite and NaOMe in DMF and 1,4-dioxane, up 99% yield were reported. This new system offers the advantage to be convenient and cost effective.

Reference: Ju, J. et al. Org. Lett. 2007, 9, 4615.

Written by: William Sommer, Ph.D

Cross- coupling reactions for the formation of carbon-nitrogen bonds is a powerful tool for the synthesis of important compounds in biological and material sciences. These reactions?are usually catalyzed using transition metals such as palladium or copper associated with a ligand. One of the drawbacks?using these metals is the cost and toxicity.?Correa and Bolm developed a new method for the N-arylation of nitrogen nucleophiles using FeCl₃?as a metal and N,N'-dimethylethylenediamine as a ligand. A typical procedure involves the use of potassium phosphate as a base and toluene as a solvent. A temperature of 134 C for 24 hours is necessary for full completion of the reaction. Prel;iminary results shows the activity of this new system for the coupling of a variety of aryl iodides with?1H-pyrazole. Up to 87% yields were reported for the N-arylation 1H-pyrazole with 1-chloro-3-iodophenyl.

Reference: Correa, A.; Bolm, C. Angew. Chem., Int. Ed. 2007, 46, 8862.

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