Coordination mode and stability of the tetrahydroborate ligand in group 10 metal pincer complexes. Issue 30 (14th July 2022)

• Record Type: Journal Article
• Authors: Chang, Jiarui; Ding, Man; Kang, Jia-Xin; Zhang, Jie; Chen, Xuenian
• Is Part Of: Dalton transactions. Volume 51:Issue 30(2022)
• Page Start: 11507
• Page End: 11514
• Publication Date: 2022-07-14
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/d2dt01357f
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : The coordination mode and stability of the tetrahydroborate ligand in group 10 metal pincer complexes are significantly influenced by the pincer platform and the electronic properties of the metal centre. Abstract : The coordination mode of the BH4 − ligand in transition metal tetrahydroborate complexes is mainly dominated by the nature of the metal centres. However, other factors can also play important roles sometimes. In order to rationalize the coordination modes and the stability of the BH4 − ligand in group 10 metal tetrahydroborate pincer complexes, [2, 6-( t Bu2 PO)2 C6 H3 ]Pt(η 1 -HBH3 ) and [C6 H4 - o -(NCH2 P t Bu2 )2 B]M(η 2 -H2 BH2 ) (M = Ni, Pt) were prepared and characterized. A structural comparison of [2, 6-( t Bu2 PCH2 )2 C6 H3 ]Ni(BH4 ), [2, 6-( t Bu2 PO)2 C6 H3 ]M(BH4 ) and [C6 H4 - o -(NCH2 P t Bu2 )2 B]M(BH4 ) (M = Ni, Pd, and Pt) indicates that the M–P bond length, the P–M–P bite angle and the trans-influence of the central atom in the pincer platform also affect the coordination mode of the BH4 − ligand. The nickel complexes tend to adopt a monodentate coordination mode while the palladium and platinum complexes can adopt either the monodentate or the bidentate mode depending on the structural features of the pincer platforms. Longer M–P bonds and smaller P–M–P bite angles favour the bidentate mode. The stability of the BH4 − ligand is influenced by both the coordination mode and the nature of the metal centre. The BH3 species is released more easily from complexes with less electron rich metal centres. Following the series of Ni, Pd, and Pt, complexes with the same pincer ligand more easily lose a BH3 moiety.