Bis(triisopropylsilyl)-o-phenylenediamido complexes of tantalum. X-ray structure of (η5-C5Me5)[o-C6H4(NSiPri3)2]TaCl2

Terminal Alkylphosphanylidene Organo­tantalum(V) Complexes

“…These Ta-P bonds are shorter than the sum of the covalent radii of Ta and P (277 pm). [12] This difference is caused by the lower steric demand of the phosphanylidene unit and the higher steric demand of the isopropyl substituents. The fold angle in the starting material 1 [129.6(1)°, see Supporting Information] is about 7°smaller than in 2 and 3 but 8°larger than that in the bis(triisopropylsilyl) derivative [Cp*Ta{1,2-(NSiiPr 3 ) 2 C 6 H 4 }Cl 2 ] (121.3°).…”

Terminal Alkylphosphanylidene Organo­tantalum(V) Complexes

“…These Ta-P bonds are shorter than the sum of the covalent radii of Ta and P (277 pm). [12] This difference is caused by the lower steric demand of the phosphanylidene unit and the higher steric demand of the isopropyl substituents. The fold angle in the starting material 1 [129.6(1)°, see Supporting Information] is about 7°smaller than in 2 and 3 but 8°larger than that in the bis(triisopropylsilyl) derivative [Cp*Ta{1,2-(NSiiPr 3 ) 2 C 6 H 4 }Cl 2 ] (121.3°).…”

Disubstituted 1,8-Diamidonaphthalene Ligands as a Flexible, Responsive, and Reactive Framework for Tantalum Complexes

“…This feature is reminiscent of the reported tungsten 3b and tin 7 complexes with the R 2 DAN 2ligand. Furthermore, it is similar to structural features that have been observed in high-valent group 4, 1g Ta, 8,9 Mo, 10 and W 11 species bearing N,N 0 -bis(trialkylsilyl)-o-phenylene diamide (PDA) ligands. In the case of the PDA complexes, the fold of the ligand about the N-N vector has been attributed to an increase in metal ligand interaction through a π donation from the phenylene component of the ligand into the metal orbitals.…”

“…In the case of the PDA complexes, the fold of the ligand about the N-N vector has been attributed to an increase in metal ligand interaction through a π donation from the phenylene component of the ligand into the metal orbitals. 8,10 In order to better understand the origin of these structural differences, we have examined 1 and 3 computationally, and the results of our analysis are presented below.…”

Synthesis and Reactivity of Ene-Diamido and Ene-Diolato [(Trimethylsilyl)cyclopentadienyl]niobium(V) Complexes and a Comparative DFT Study of the Bonding Capabilities of Diazabutadiene and Butadiene Ligands

“…The adoption of a particular conformation depends on the coordination environment on the metal centre and the steric properties of the substituents of the DAD ligand. In most of the dichloro compounds this ligand adopts a supine conformation, except for a bulky substituted t Bu,H‐DAD derivative [TaCp*Cl 2 ( t Bu,H‐DAD)]13e and for the bis(trialkylsilyl)‐ o ‐phenylenediamido complexes, [TaCp*Cl 2 {( i Pr 3 SiN) 2 ‐ o ‐C 6 H 4 }]14a and [M{η 5 ‐C 5 H 3 (SiMe 3 ) 2 }Cl 2 {(Me 3 SiN) 2 ‐ o ‐C 6 H 4 }]14b (M = Nb, Ta). On the basis of the steric properties of the ligands and the NMR spectroscopic data of complexes 1 − 3 we conclude that both ene‐diamido and ene‐diolato ligands adopt the supine conformation (see Scheme ).…”

Terminal Alkylphosphanylidene Organo­tantalum(V) Complexes

“…These Ta-P bonds are shorter than the sum of the covalent radii of Ta and P (277 pm). [12] This difference is caused by the lower steric demand of the phosphanylidene unit and the higher steric demand of the isopropyl substituents. The fold angle in the starting material 1 [129.6(1)°, see Supporting Information] is about 7°smaller than in 2 and 3 but 8°larger than that in the bis(triisopropylsilyl) derivative [Cp*Ta{1,2-(NSiiPr 3 ) 2 C 6 H 4 }Cl 2 ] (121.3°).…”

Disubstituted 1,8-Diamidonaphthalene Ligands as a Flexible, Responsive, and Reactive Framework for Tantalum Complexes

“…This feature is reminiscent of the reported tungsten 3b and tin 7 complexes with the R 2 DAN 2ligand. Furthermore, it is similar to structural features that have been observed in high-valent group 4, 1g Ta, 8,9 Mo, 10 and W 11 species bearing N,N 0 -bis(trialkylsilyl)-o-phenylene diamide (PDA) ligands. In the case of the PDA complexes, the fold of the ligand about the N-N vector has been attributed to an increase in metal ligand interaction through a π donation from the phenylene component of the ligand into the metal orbitals.…”

“…In the case of the PDA complexes, the fold of the ligand about the N-N vector has been attributed to an increase in metal ligand interaction through a π donation from the phenylene component of the ligand into the metal orbitals. 8,10 In order to better understand the origin of these structural differences, we have examined 1 and 3 computationally, and the results of our analysis are presented below.…”

Synthesis and Reactivity of Ene-Diamido and Ene-Diolato [(Trimethylsilyl)cyclopentadienyl]niobium(V) Complexes and a Comparative DFT Study of the Bonding Capabilities of Diazabutadiene and Butadiene Ligands

“…The adoption of a particular conformation depends on the coordination environment on the metal centre and the steric properties of the substituents of the DAD ligand. In most of the dichloro compounds this ligand adopts a supine conformation, except for a bulky substituted t Bu,H‐DAD derivative [TaCp*Cl 2 ( t Bu,H‐DAD)]13e and for the bis(trialkylsilyl)‐ o ‐phenylenediamido complexes, [TaCp*Cl 2 {( i Pr 3 SiN) 2 ‐ o ‐C 6 H 4 }]14a and [M{η 5 ‐C 5 H 3 (SiMe 3 ) 2 }Cl 2 {(Me 3 SiN) 2 ‐ o ‐C 6 H 4 }]14b (M = Nb, Ta). On the basis of the steric properties of the ligands and the NMR spectroscopic data of complexes 1 − 3 we conclude that both ene‐diamido and ene‐diolato ligands adopt the supine conformation (see Scheme ).…”

Terminal Alkylphosphanylidene Organo­tantalum(V) Complexes

“…These Ta-P bonds are shorter than the sum of the covalent radii of Ta and P (277 pm). [12] This difference is caused by the lower steric demand of the phosphanylidene unit and the higher steric demand of the isopropyl substituents. The fold angle in the starting material 1 [129.6(1)°, see Supporting Information] is about 7°smaller than in 2 and 3 but 8°larger than that in the bis(triisopropylsilyl) derivative [Cp*Ta{1,2-(NSiiPr 3 ) 2 C 6 H 4 }Cl 2 ] (121.3°).…”

Disubstituted 1,8-Diamidonaphthalene Ligands as a Flexible, Responsive, and Reactive Framework for Tantalum Complexes

“…This feature is reminiscent of the reported tungsten 3b and tin 7 complexes with the R 2 DAN 2ligand. Furthermore, it is similar to structural features that have been observed in high-valent group 4, 1g Ta, 8,9 Mo, 10 and W 11 species bearing N,N 0 -bis(trialkylsilyl)-o-phenylene diamide (PDA) ligands. In the case of the PDA complexes, the fold of the ligand about the N-N vector has been attributed to an increase in metal ligand interaction through a π donation from the phenylene component of the ligand into the metal orbitals.…”

“…In the case of the PDA complexes, the fold of the ligand about the N-N vector has been attributed to an increase in metal ligand interaction through a π donation from the phenylene component of the ligand into the metal orbitals. 8,10 In order to better understand the origin of these structural differences, we have examined 1 and 3 computationally, and the results of our analysis are presented below.…”

Synthesis and Reactivity of Ene-Diamido and Ene-Diolato [(Trimethylsilyl)cyclopentadienyl]niobium(V) Complexes and a Comparative DFT Study of the Bonding Capabilities of Diazabutadiene and Butadiene Ligands

“…The adoption of a particular conformation depends on the coordination environment on the metal centre and the steric properties of the substituents of the DAD ligand. In most of the dichloro compounds this ligand adopts a supine conformation, except for a bulky substituted t Bu,H‐DAD derivative [TaCp*Cl 2 ( t Bu,H‐DAD)]13e and for the bis(trialkylsilyl)‐ o ‐phenylenediamido complexes, [TaCp*Cl 2 {( i Pr 3 SiN) 2 ‐ o ‐C 6 H 4 }]14a and [M{η 5 ‐C 5 H 3 (SiMe 3 ) 2 }Cl 2 {(Me 3 SiN) 2 ‐ o ‐C 6 H 4 }]14b (M = Nb, Ta). On the basis of the steric properties of the ligands and the NMR spectroscopic data of complexes 1 − 3 we conclude that both ene‐diamido and ene‐diolato ligands adopt the supine conformation (see Scheme ).…”