Molybdenum Complexes Supported by PN³P Pincer Ligands: Synthesis, Characterization, and Application to Synthetic Nitrogen Fixation

Abstract

Three PN 3 P pincer ligands with a central pyridine ring, amine groups in the ligand backbone and different substituents at the terminal phosphine donors are synthesized and coordinated to molybdenum(III) precursors. Conversion of the resulting Mo III compounds to dinitrogen complexes is investigated and compared to the literature-known complex trans-[Mo(N 2 ) 2 (PMe 2 Ph)(PNP tBu )] supported by a classic PNP pincer ligand. The difference between PN 3 P ligands terminated by di- [a]

Synthesis and structural characterization of Ti(III) and Mo(III) complexes supported by PNP pincer ligands

“…The same pattern is observed for the P-M-P angles (154.37(2)° in 1 and 156.1(1)° in 2). This feature is also observed in other M(III) complexes (M = V [11,12], Cr [12,37,38], Mo [27], Ru [39], and In [40] were synthesized and characterized. The solid-state molecular structures of both complexes were determined by single-crystal X-ray diffraction and reveal distorted octahedral geometries.…”

“…These complexes were found to catalyse the homocoupling of phenylmagnesium bromide in the presence of iodomethane as an oxidising agent, at room temperature, to give phenylbenzene [12]. Although a variety of molybdenum complexes in several oxidation states can be found in the literature [13][14][15][16][17][18][19][20][21][22][23][24][25], Mo(III) complexes are scarcely reported [26][27][28]. In the presence of CoCp*2 (Cp* = η 5 -C5H5) as a reducing agent and 2,4,6-colidinium trifluoromethanesulfonate as a proton source, complexes of the formula [(R-PNP R' )MoI3] (R = H, Ph, Me, MeO, ferrocenyl, and ruthenocenyl; R' = t Bu, i Pr, Ph, and adamantyl) were effective catalysts to produce ammonia from molecular dinitrogen under ambient conditions [28].…”

Recent Progress with Pincer Transition Metal Catalysts for Sustainability

“…Tuczek reported in 2018 new molybdenum complexes bearing a PN 3 P pincer ligand with various substituents on both metal center and pincer arms [724]. The authors investigated the reactivity with N 2 through the formation of dinitrogen-bridged species based on the classic Nishibayashi Mo-PNP catalysts showed before.…”