Functionalized palladium(II) cyclometallated complexes. Crystal and molecular structures of [Pd{3-(CHO)C6H3C(H)NCy}(μ-O2CMe)]2 and [Pd{3-(CHO)C6H3C(H)NCy}(Cl)(PR3)] (PR3=PEtPh2, and PEt2Ph)

Syntheses, Structures, and Reactivities of Novel Palladium β-Diiminato−Acetate Complexes

“…Our attempts to prepare [Pd(Ph 2 nacnac)Cl] 2 from 1a via OAc − /Cl − exchange were unsatisfactory. Thus, the usual approaches for this transformation (e.g., treating 1a with MCl (M = Li, Na) in water, acetone, or mixed solvent systems (water/acetone, water/MeOH, or water/EtOH) − did not produce the desired product. Rather 1a was recovered along with unidentified species after 24∼42 h. Only small amount of [Pd(Ph 2 nacnac)Cl] 2 was isolated (∼10% yield after recrystallization) by treating 1a with NaCl in a CH 2 Cl 2 /water biphasic system in the presence of a phase-transfer catalyst n Bu 4 NCl.…”

New developments in the studies of the reactivity of cyclometallated palladium(II) compounds with homo- ([P,P],[As,As]) and heterobidentate ([P,N],[P,O]) ligands

“…Tetradentate [C,N,C,N] Schiff bases generally undergo double metallation to give compounds with two metal atoms per organic ligand [6][7][8][9][10][11][12][13][14][15][16], however, as we have reported previously, in the case of the potentialy tetradentate ligands derived from isophthalaldehyde, 1,3-(CyN@CH) 2 C 6 H 4 , and terephthalaldehyde, 1,4-(CyN@CH) 2 conditions [17][18][19]. Thus, treatment with palladium(II) acetate in acetic acid gave the monocyclometallated complexes 1 and 2 after cleavage of one C@N double bond, and we have studied the reactivity of these cyclometallated complexes towards different mono and bidentate ligands [20][21][22][23][24]. Herein, we present further developments of our investigations regarding the reactivity of 1 and 2 with the new group 15 donor atom bidentate ligands: the diphosphines, 1,2-bis(di-o-tolylphosphino)ethane and 4-(diphenylphosphino)-2-(diphenylphosphinomethyl)pyrrol, as well the diarsine: 1,2-bis(diphenylarsino)ethane.…”

Reactivity of cyclopalladated compounds derived from biphenyl-2-ylamine towards carbon monoxide, tbutyl isocyanide and alkynes

“…As expected (i) the carbon-carbon distances of the alkene units coordinated g 2 to the palladium(II) centres were larger than the carbon-carbon distances of the alkene units coordinated j 1 to the palladium(II) centres À1.409(3) Å and 1.325(3) Å for compound 5 and 1.387(6) Å and 1.376 (7) Å for compound 6 -and (ii) the alkene units coordinated g 2 to the palladium(II) centre were no longer planar -the dihedral angles C14-C13-C20-C21 for compound 5 and C14-C13-C16-C17 for compound 6 were 152.1(2)°a nd 164.5(4)°, respectively. The Pd-Cl distances -2.3157(6) Å for compound 5 and 2.328(3) Å for compound 6 -and the Pd-N distances -2.1810(19) Å for compound 5 and 2.196(4) Å for compound 6 -were shorter and longer, respectively, than the analogous distances in mononuclear cyclopalladated compounds of general formula trans-N,P-[Pd(C,N)Cl(phosphine)] [49][50][51]. This is due to the weaker trans influence of an g 2 -coordinated alkene in relation to a metallated carbon atom and to the stronger trans influence of a metallated carbon atom in relation to a phosphine ligand [52].…”