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Updated: May 20, 2026

Experimental Approaches for the Synthesis of Low-Valent Metal-Organic Frameworks from Multitopic Phosphine Linkers
Published on: May 12, 2023
Conformational analysis of triphenylphosphine in square planar organometallic complexes: [(PPh3)(ML1L2L3)] and
1Department of Chemistry, University of the Free State, Bloemfontein, 9301, Republic of South Africa. conradj@ufs.ac.za
Abstract:
The conformation analysis of free PPh(3) and PPh(3) coordinated to tetrahedral, trigonal-bipyramidal, octahedral or square planar achiral metal centres is discussed. Results from ADF calculations, in agreement with experimental structures, show that favoured degenerate conformations of complex-bound PPh(3) in square planar [(PPh(3))(ML(1)L(2)L(3))] and [M(acac)(L')(PPh(3))] complexes can be obtained by applying the following principles (P helicity, view along P-M axis), (i) superimpose C(ortho) of the vertical ring A onto the nadir plane perpendicular to the square plane and allow ring A to tilt towards the smallest ligand, (ii) allow ring B to tilt in the space below the smallest ligand in the quadrant between the nadir plane below the complex and a horizontal plane through the SQP of the complex, (iii) tilt ring C over the largest ligand and (iv) allow correlated tilting of rings A, B and C to minimize inter ring-ring and inter ring-ligand interactions.
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