金（III）配合物中的胺 - 酰胺平衡与金（III）-金（I）亲金键

Amine-amide equilibrium in gold(III) complexes and a gold(III)-gold(I) aurophilic bond.

作者信息

Cao Lingyun, Jennings Michael C, Puddephatt Richard J

机构信息

Department of Chemistry, University of Western Ontario, London, Canada N6A 5B7.

出版信息

Inorg Chem. 2007 Feb 19;46(4):1361-8. doi: 10.1021/ic061911y.

DOI:10.1021/ic061911y

PMID:17291122

Abstract

The ligands HN(CH2-2-C5H4N)2, BPMA, and PhCH2N(CH2-2-C5H4N)2, BBPMA, react with Na[AuCl4] to give the cationic complexes [AuCl(BPMA-H)]+ and [AuCl(BBPMA)]2+, respectively. The amido complex [AuCl(BPMA-H)]+ undergoes easy inversion at the amido nitrogen atom and can be reversibly protonated by triflic acid to give [AuCl(BPMA)]2+. The complex [AuCl(BBPMA)]2+ is easily decomposed in aqueous solution by cleavage of a carbon-nitrogen bond or, in dilute HCl solution, by protonation of the ligand to give [BBPMAH2]Cl[AuCl4] The complexes [BBPMAH2]Cl[AuCl4] and [BBPMAH2]Cl[AuCl2] can be formed by direct reaction of BBPMA with H[AuCl4]. Unusual forms of gold(III)...gold(III) and gold(III)...gold(I) aurophilic bonding are observed in the salts [AuCl(BPMA-H)][PF6] and [AuCl(BPMA-H)][AuCl2], respectively. The first comparison of the structures of gold(III) amine and amido complexes, in the cations [AuCl(BPMA-H)]+ and [AuCl(BPMA)]2+, indicates that there is little ppi-dpi bonding in the amido-gold bond and that the amide exerts a stronger trans influence than the amine group.

摘要

配体HN(CH₂-2-C₅H₄N)₂（BPMA）和PhCH₂N(CH₂-2-C₅H₄N)₂（BBPMA）分别与Na[AuCl₄]反应，生成阳离子配合物[AuCl(BPMA-H)]⁺和[AuCl(BBPMA)]²⁺。酰胺基配合物[AuCl(BPMA-H)]⁺在酰胺氮原子处容易发生反转，并且可以被三氟甲磺酸可逆质子化，生成[AuCl(BPMA)]²⁺。配合物[AuCl(BBPMA)]²⁺在水溶液中容易通过碳氮键的断裂而分解，或者在稀盐酸溶液中，通过配体的质子化生成[BBPMAH₂]Cl[AuCl₄]。配合物[BBPMAH₂]Cl[AuCl₄]和[BBPMAH₂]Cl[AuCl₂]可以通过BBPMA与H[AuCl₄]直接反应形成。在盐[AuCl(BPMA-H)][PF₆]和[AuCl(BPMA-H)][AuCl₂]中分别观察到了不寻常形式的金(III)……金(III)和金(III)……金(I)亲金相互作用。阳离子[AuCl(BPMA-H)]⁺和[AuCl(BPMA)]²⁺中金(III)胺和酰胺基配合物结构的首次比较表明，酰胺-金键中几乎没有π键-δ键相互作用，并且酰胺比胺基具有更强的反位影响。