Preparation and electrochemical reactions of nickel(II) complexes containing isocyanide and mono- or di-phosphines

Four- and five-coordinate nickel(ii) complexes bearing new diphosphine–phosphonite and triphosphine–phosphite ligands: catalysts for N-alkylation of amines

“…The five coordinate τ 5 value is 0.53, suggesting that the structure lies in the middle of two extreme ideal structures - trigonal bipyramidal ( τ 5 = 1) and square pyramidal ( τ 5 = 0) and is best described as a distorted trigonal bipyramidal geometry. The variation in the Ni–P distances (2.1953(11), 2.1459(12) and 2.2118(12) Å) are similar to complex 3 and also to those found in the reported five-coordinate Ni( ii ) complexes: [Ni(CN) 2 (PhP{CH 2 CH 2 PPh 2 } 2 )], 38 [NiCl(dppp)(XylNC) 2 ] + , 39 [Ni{1,2-bis(bis(hydroxypropyl)phosphino)ethane} 2 Cl] + , 40 [NiCl{bis(dimethylphosphino)ethane} 2 ] + , 41 [NiCl( P , P ′-diphenyl-1,4-diphosphacyclohexane) 2 ] + , 42 and [NiCl(1,5-diphenyl-1,5-diphosphacyclooctane) 2 ] + . 43 …”

“…This is supported by the C33-N1 distance of 1.149(5) Å which is close to 1.161(1) Å found in the free XylylNC. 46 The Ni-C XylylNC bond length of 1.841(5) Å is similar to those found in the ve coordinate Ni(II) complexes such as [NiCl(dppp 39 and [NiCl{C(NCH 2 -PPh 2 ) 2 (CH 2 ) 3 -k 3 P,C,P 0 }(XylylNC)][PF 6 ] (1.831(2) Å). 47 The Ni-Cl distance of 2.352(1) Å is rather far from the sum of the covalent radii of Ni (1.24 Å) and Cl (1.02 Å) atoms; however, it falls within the sum of the van der Waals radii (Ni ¼ 1.63 Å and Cl ¼ 1.75 Å) and is similar to the distances found in the reported complexes.…”

“…47 The Ni-Cl distance of 2.352(1) Å is rather far from the sum of the covalent radii of Ni (1.24 Å) and Cl (1.02 Å) atoms; however, it falls within the sum of the van der Waals radii (Ni ¼ 1.63 Å and Cl ¼ 1.75 Å) and is similar to the distances found in the reported complexes. 39,[41][42][43]47,48 Complex 6 and 7 crystallize in the monoclinic space group P2 1 /n and their asymmetric units consist of the whole molecule and one dichloromethane. ORTEP views along with selected bond lengths and angles are shown in Fig.…”

Crystal structure and DFT analyses of a pentacoordinated PCP pincer nickel(II) complex

“…The Cg1Á Á ÁCg1 i distance is 3.6620 (15) Å , the interplanar distance is 3.4859 (15) Å and the offset is 1.1220 (11) Å [Cg1 is the centroid of the C32/C33/C35-C38 ring; symmetry code: (i) Àx + 1, Ày, Àz + 1]. 3the reported spectra of pentacoordinated Ni II complexes containing two phosphane, two carbon and one chloride donors (Alyea et al, 1972;Cloyd & Meek, 1972;Yamamoto et al, 1997). There is no significant change in the absorption spectrum, even in coordinating solvents, such as MeCN, THF and EtOH, supporting further that the chloride ion is strongly bound to the Ni atom.…”

“…(2019). C75, 734-739 Schematic representation of the chlorine orbital interactions in 1, showing (a) Cl LP1 and Ni LP* , (b) Cl LP2 , C LP* and Ni LP* , and (c) Cl LP3 , C LP* and Ni LP* .complexes, namely [NiCl{bis(diphenylphosphino)propane}-(XylylNC) 2 ] + ( = 0.265;Yamamoto et al, 1997), ) 2 (XylylNC) 2 ] + ( = 0.032;Yamamoto et al, 1997), [NiCl{bis(dimethylphosphino)ethane} 2 ] + ( = 0.010;Handley et al, 2001), [NiCl(1,4-diphenyl-1,4-diphosphacyclohexane) 2 ] + ( = 0.173;…”