A triazine-based Ni(II) PNP pincer complex as catalyst for Kumada–Corriu and Negishi cross-coupling reactions

Kumada–Corriu and Negishi cross-coupling reactions, catalyzed efficiently by a Ni(II) PNP pincer complex containing a triazine backbone, are described. The catalyst is able to react with both activated and inactivated aryl halides including chlorides as well as phenol derivatives such as tosylates and mesylates to give the corresponding cross-coupling products in good to excellent isolated yields. A high diversity of substrates was tested under moderate conditions for both types of reactions.Austrian Science Fund (FWF

Crystal structure of the tetrahydrofuran disolvate of a 94:6 solid solution of [N2,N6-bis(di-tert-butylphosphanyl)pyridine-2,6-diamine]dibromidomanganese(II) and its monophosphine oxide analogue

The MnBr2 complex of N2,N6-bis(di-tert-butylphosphanyl)pyridine-2,6-diamine (1·MnBr2) co-crystallizes with 5.69% of the monophosphine oxide analogue (1O·MnBr2) and two tetrahydrofuran (THF) molecules, namely [N2,N6-bis(di-tert-butylphosphanyl)pyridine-2,6-diamine]dibromidomanganese(II)–[bis(di-tert-butylphosphanyl)({6-[(di-tert-butylphosphanyl)amino]pyridin-2-yl}amino)phosphine oxide]dibromidomanganese(II)–tetrahydrofuran (0.94/0.06/2), [MnBr2(C21H41N3P2)]0.94[MnBr2(C21H41N3OP2)]0.06·2C4H8O. The 1·MnBr2 and 1O·MnBr2 complexes are occupationally disordered about general positions. Both complexes feature square-pyramidal coordination of the MnII atoms. They are connected by weak N—H...Br hydrogen bonding into chains extending along [001]. The THF molecules are located between the layers formed by these chains. One THF molecule is involved in hydrogen bonding to an amine H atom

Sustainable Synthesis of Quinolines and Pyrimidines Catalyzed by Manganese PNP Pincer Complexes

This study represents the first example an environmentally benign, sustainable, and practical synthesis of substituted quinolines and pyrimidines using combinations of 2-aminobenzyl alcohols and alcohols as well as benzamidine and two different alcohols, respectively. These reactions proceed with high atom efficiency via a sequence of dehydrogenation and condensation steps that give rise to selective C–C and C–N bond formations, thereby releasing 2 equiv of hydrogen and water. A hydride Mn­(I) PNP pincer complex recently developed in our laboratory catalyzes this process in a very efficient way. A total of 15 different quinolines and 14 different pyrimidines were synthesized in isolated yields of up to 91 and 90%, respectively

A Convenient Solvothermal Synthesis of Group 6 PNP Pincer Tricarbonyl Complexes

The solvothermal synthesis of a series of zerovalent Cr, Mo, and W complexes of the type [M­(PNP)­(CO)₃] featuring PNP pincer ligands based on 2,6-diaminopyridine is described. We demonstrate that the solvothermal synthesis technique presented provides a powerful, simple, and practical synthetic method resulting in high isolated yields in a short time. In particular, Cr and W complexes are not readily accessible via conventional methods. Moreover, this study allows a direct comparison of steric and electronic properties of group 6 metal PNP pincer tricarbonyl complexes