Reaction of coordinated isocyanides with substituted N -(2-pyridyl) ureas as a route to new cyclometallated Pd(II) complexes

Substituted N-(pyridin-2-yl) ureas or carbamates act as polynucleophiles upon the reaction with palla-dium(II) bis(isocyanide) complexes at RT to give metallacycles containing azaheterocyclic and urea frag-ments. Nine new C,N-chelate deprotonated diaminocarbene palladium(II) complexes were synthesized by coupling substituted N-(2-pyridyl)ureas and coordinated isocyanides. The obtained yellow or green-yellow species were characterized by high-resolution mass spectrometry and 1D ( 1 H, 13 C) NMR spectroscopies. The structures of six complexes in a solid state were elucidated by single-crystal X-ray diffraction (XRD). This universal and convenient method for the preparation of C <<^>> N-cyclometallated palladium(II) complexes under mild conditions opens the way to the targeted synthesis of polyfunctional organometallic com-pounds that combine the chemical, biological, and photophysical properties of metallacycles and parent azaheterocycles.(c) 2022 Elsevier B.V. All rights reserved.

Automated summary

Substituted N-(pyridin-2-yl) ureas or carbamates can act as polynucleophiles and react with palladium(II) bis(isocyanide) complexes to form metallacycles containing azaheterocyclic and urea fragments. Nine new C,N-chelate deprotonated diaminocarbene palladium(II) complexes were synthesized by coupling substituted N-(2-pyridyl)ureas and coordinated isocyanides. This method provides a convenient way for the targeted synthesis of polyfunctional organometallic compounds.