The reaction of in situ generated 1'-(diphenylphosphino)-1-lithioferrocene with carbamoyl chlorides, ClC(E)NMe2, affords the corresponding (thio)amides, Ph2PfcC(E)NMe2 (E = O (), S (); fc = ferrocene-1,1'-diyl). These compounds as well as their analogues, Ph2PfcC(O)NHMe () and Ph2PfcC(O)NH2 (), prepared from 1'-(diphenylphosphino)ferrocene-1-carboxylic acid (Hdpf) were studied as ligands for the Group 11 metal ions. In the reactions with [Cu(MeCN)4][BF4], the amides give rise to bis-chelate complexes of the type [Cu(L-κ(2)O,P)2][BF4]. Similar products, [Ag(L-κ(2)O,P)2]ClO4, are obtained from silver(i) perchlorate and , or . In contrast, the reaction of AgClO4 with produces a unique molecular dimer [Ag()(ClO4-κO)]2, where the metal centres are bridged by the sulfur atoms of the P,S-chelating thioamides. The reactions of with [AuCl(tht)] (tht = tetrahydrothiophene) afford the expected gold(i)-phosphine complexes, [AuCl(L-κP)], containing uncoordinated (thio)amide moieties. Hemilabile coordination of the phosphinoamide ligands in complexes with the soft Group 11 metal ions is established by the crystal structure of a solvento complex, [Cu(-κ(2)O,P)(-κP)(CHCl3-κCl)][BF4], which was isolated serendipitously during an attempted crystallisation of [Cu(-κ(2)O,P)2][BF4]. All of the compounds are characterised by spectroscopic methods, and the structures of several representatives of both the free phosphinoamides and their complexes are determined by X-ray diffraction analysis and further studied by DFT calculations and cyclic voltammetry.

New phosphinoferrocene ligands bearing extended polar amidourea pendants with the general formula Ph 2 PfcCONHCH 2 CH 2 NHCONR 2 (1; R 2 = H 2 (b), H/Et (c), Me 2 (d), H/Ph (e)) and their model bis-amide Ph 2 PfcCONHCH 2 CH 2 NHCOCH 3 (1a) were prepared in good yields by amidation of 1′-(diphenylphosphino)ferrocene-1-carboxylic acid (Hdpf) with the appropriate amines in the presence of peptide coupling reagents. These ferrocene-based phosphinoureas were further employed as ligands in palladium(II) complexes with η 3 -allyl and NCchelating supporting ligands: viz., [). Both the free ligands and their Pd(II) complexes were characterized by spectroscopic methods (multinuclear NMR, IR, and MS) and by elemental analysis. The molecular structures of 1b•CH 3 OH, 1c, 5b,c, 6a, and two additional model complexes, [PdCl(η 3 -C 3 H 5 )(Hdpf-κP)] (5f) and [PdCl(η 3 -C 3 H 5 )(Ph 2 PfcCONH 2 -κP)] (5g), were determined by single-crystal X-ray diffraction analysis. All Pd(II) complexes were evaluated as catalysts in the cross-coupling of boronic acids and acyl halides to give ketones in a toluene/water biphasic mixture. Extensive reaction studies with compound 5e, which not only exerts good catalytic activity but is also readily accessible in a defined crystalline form, demonstrated efficient coupling reactivity for unsaturated substrates such as (substituted) benzeneboronic acids and benzoyl chlorides. The results also revealed that reaction difficulties encountered with less reactive substrates (e.g., insoluble aromatic boronic acids and all saturated aliphatic boronic acids) can be avoided by properly selecting the reaction partners, for example through transposition of substituents between reaction partners. Three representative benzophenones (4-fluoro-, 4-nitro-, and 4,4′-dinitrobenzophenone) were structurally characterized by single-crystal X-ray crystallography.

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