Vogt, Matthias’s team published research in Organometallics in 32 | CAS: 338800-13-8

Organometallics published new progress about 338800-13-8. 338800-13-8 belongs to pyridine-derivatives, auxiliary class Bis-phosphine Ligands, name is 2,6-Bis((di-tert-butylphosphino)methyl)pyridine, and the molecular formula is C21H20BrNO4S, Category: pyridine-derivatives.

Vogt, Matthias published the artcileAnionic Nickel(II) Complexes with Doubly Deprotonated PNP Pincer-Type Ligands and Their Reactivity toward CO2, Category: pyridine-derivatives, the publication is Organometallics (2013), 32(1), 300-308, database is CAplus.

The aromatization-dearomatization reaction of pincer-type complexes prompted by protonation-deprotonation of the pincer “arm” is a key step in bond activation chem. and atom-economic catalytic transformations. However, the possibility of double deprotonation of ancillary pincer ligands is rarely discussed in the literature. Here authors report on square-planar cationic nickel(II) complexes of PNPR type ligands (PNP = 2,6-bis[(dialkylphosphino)methyl]pyridine with R = iPr, tBu), which can be readily transformed into the doubly deprotonated anionic species. The complexes [Ni(PNPR)Cl]Cl (3, R = iPr; 4, R = tBu) are readily prepared from the reaction of NiCl2·6H2O and the PNPR ligand in THF. Treatment of the cationic chloro complexes 3 and 4 with 2 equivalent of MeLi gives the nickel(II) Me complexes [Ni(PNPR*)Me] (7, R = iPr; 8, R = tBu), the asterisk indicates the deprotonated pincer arm. Reaction of 7 and 8 with an addnl. 1 equivalent of MeLi gives the anionic complexes [Li(DME)3][Ni(PNPiPr**)Me] (9-DME, DME = 1,2-dimethoxyethane) and [Li(Et2O)2][Ni(PNPtBu**)(Me)] (10-Et2O), resp. Single-crystal x-ray diffraction studies exhibit doubly deprotonated PNP-pincer ligands coordinated to a nickel(II) center. DFT calculations, as well as multinuclear NMR spectroscopy and the x-ray structures, suggest a conjugated π-system with delocalization of the neg. charge throughout the carbon backbone of the pincer ligand. The electrophilic attack of complex 9 by CO2 and tautomerization gives [Li][Ni(PNPiPr*-COO)(Me)] (11). The dearomatized complex that is formed contains an exocyclic methylene carbon atom and a carboxylate moiety adjacent to the second pincer arm.

Organometallics published new progress about 338800-13-8. 338800-13-8 belongs to pyridine-derivatives, auxiliary class Bis-phosphine Ligands, name is 2,6-Bis((di-tert-butylphosphino)methyl)pyridine, and the molecular formula is C21H20BrNO4S, Category: pyridine-derivatives.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem