116080-41-2Relevant academic research and scientific papers
Rhodium and palladium complexes of a pyridyl-centred polyphenylene derivative
Ollagnier, Cecile M. A.,Perera, Sarath D.,Fitchett, Christopher M.,Draper, Sylvia M.
, p. 283 - 290 (2008)
2-(2′-Pyridyl)-3,4,5,6-tetraphenylpyridine 2 (HL), a ligand with both N,N-bidentate and N,N,C-terdentate coordination potential, was prepared in excellent yield by the Diels-Alder [2+4] cycloaddition of 2-cyanopyridine and tetraphenylcyclopentadien-1-one. Monometallic Pd(ii) and Rh(iii) complexes were formed which exhibit both types of ligand coordination (trans-[RhCl 2(L)(NCMe)] 3, cis-[RhCl(L)(NCMe)2]PF64, cis-[RhCl2(HL)2]PF66, [RhCl(L)(HL)]PF 67, [Rh(L)2]PF68, [Pd(OAc)(L)] 9 and [Pd(η3-methallyl)(HL)]PF610). The molecular structures of the ligand and six complexes, including the chloro-bridged dimer [RhCl(L)(μ-Cl)]25, were obtained by single crystal X-ray diffraction. The Royal Society of Chemistry 2008.
Robust Cobalt Catalyst for Nitrile/Alkyne [2+2+2] Cycloaddition: Synthesis of Polyarylpyridines and Their Mechanochemical Cyclodehydrogenation to Nitrogen-Containing Polyaromatics**
Wang, Chang-Sheng,Sun, Qiao,García, Felipe,Wang, Chen,Yoshikai, Naohiko
supporting information, p. 9627 - 9634 (2021/03/19)
The transition-metal-catalyzed [2+2+2] cycloaddition of nitriles and alkynes is an established synthetic approach to pyridines; however, these cycloadditions often rely on the use of tethered diynes or cyanoalkynes as one of the reactants. Thus, examples of efficient, fully intermolecular catalytic [2+2+2] pyridine synthesis, especially those employing unactivated nitriles and internal alkynes leading to pentasubstituted pyridines, remain scarce. Herein, we report on simple and inexpensive catalytic systems based on cobalt(II) iodide, 1,3-bis(diphenylphosphino)propane, and Zn that promote [2+2+2] cycloaddition of various nitriles and diarylacetylenes for the synthesis of a broad range of polyarylated pyridines. DFT studies support a reaction pathway involving oxidative coupling of two alkynes, insertion of the nitrile into a cobaltacyclopentadiene, and C-N reductive elimination. The resulting tetra- and pentaarylpyridines serve as precursors to hitherto unprecedented nitrogen-containing polycyclic aromatic hydrocarbons via mechanochemically assisted multifold reductive cyclodehydrogenation.
