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Readily available phosphinoferrocene guanidines coordinate Pd(II) as P,N-chelating or κ3P,N,Fe-bound ligands. As the latter, they give rise to the first donor-asymmetric complexes featuring Fe–Pd dative bonds, which were studied using direct (spectroscopic and electrochemical) methods and theoretical (DFT) approaches. [ABSTRACT FROM AUTHOR]

A series of cationic Pt(II) complexes with chelating bis‐carbene and P,P‐ or P,S‐ligands, viz. [(C^C)Pt(X^Y)][BF4]2 (2a–e), where C^C = methylenebis(3‐methyl‐1H‐imidazol‐1‐yl‐2‐ylidene, and X^Y = Ph2PCH2CH2PPh2 (dppe) (a), Ph2P(CH2)3PPh2 (dppp) (b), 1,2‐(Ph2P)2C6H4 (dppbz) (c), [Fe(η5‐C5H4PPh2)2] (dppf) (d), and Ph2PCH2CH2SPh (e), were synthesized and structurally characterized by NMR and MS spectroscopy and by single‐crystal X‐ray diffraction analysis. Furthermore, photophysical measurements showed that these compounds were non‐emissive at room temperature. However, when cooled to 77 K, compounds 2a, 2b and 2c showed weak luminescence in the near UV region with emission maxima in the 380–395 nm range. [ABSTRACT FROM AUTHOR]

This contribution expands the still narrow class of functional ferrocene phosphanes with polar cationic groups, focusing on the synthesis and catalytic use of a series of phosphanylferrocene ligands bearing positively charged guanidinium tags, [R2PfcCH2NHC(NH2)2]Cl (3a–d), where fc = ferrocene‐1,1′‐diyl, R = isopropyl (a), cyclohexyl (b), phenyl (c), and 2‐furyl (d). To probe the influence of phosphane substituents, these compounds were studied as supporting ligands in Pd‐catalyzed Suzuki–Miyaura cross‐coupling of acyl chlorides with arylboronic acids, in analogous coupling of aryl bromides with arylboronic acids, and in Rh‐catalyzed hydroformylation of 1‐hexene using trans‐[RhCl(CO){R2PfcCH2NHC(NH2)2‐κP}2]Cl2 complexes (4a–d) as pre‐catalysts. The outcome of the cross‐coupling reactions strongly depended on the starting materials, and no ligand generated a universally applicable catalyst when combined with Pd(OAc)2. In the hydroformylation reactions, the catalyst based on 4d led to lower conversions than all others, which performed rather similarly. Overall, the phenyl‐substituted phosphane 3c emerged as a good compromise, giving rise to reasonably efficient and stable catalysts in most cases (except for Suzuki–Miyaura biaryl cross‐couplings, wherein electron‐rich alkylphosphanes performed better than 3c). [ABSTRACT FROM AUTHOR]

Gold(i) phosphine complexes are often used in catalysis, but the role of their auxiliary ligands still remains poorly understood. Thus, building on our previous research, we prepared a series of Au(i) complexes [Au2(μ-R2PfcCN)2][SbF6]2 (fc = ferrocene-1,1′-diyl) to assess the effect of phosphine groups PR2 on the catalytic properties of these highly catalytically active, dimeric compounds. Catalytic testing in Au-mediated cyclisation of N-propargyl amides to 2-substituted 5-methyleneoxazolines showed that weaker donating phosphines gave rise to more active, albeit partly destabilised, catalysts. Nevertheless, thanks to their self-stabilisation by reversible nitrile coordination, [Au2(μ-R2PfcCN)2]+ cations readily converted into catalytically active species (by dissociation) and, in addition, remained catalytically active even at very low metal loadings. The experimental results were supported by the trends in 1JPSe coupling constants for R2P(Se)fcCN as a measure of ligand basicity, and by DFT calculations. [ABSTRACT FROM AUTHOR]

[1′-(Diphenylphosphino)ferrocenyl]methylamine ( 1 ) reacts with Ph 2 PH/(CH 2 O) x or [Ph 2 P(CH 2 OH) 2 ]Cl to give mixtures of Ph 2 PfcCH 2 NHCH 2 PPh 2 and Ph 2 PfcCH 2 N(CH 2 PPh 2 ) 2 in which the triphosphine dominates (fc = ferrocene-1,1′-diyl). To avoid unwanted two-fold phosphinomethylation, the amine group in 1 was alkylated. As expected, the reaction of the N -methyl analogue Ph 2 PfcCH 2 NHMe ( 5 ), obtained by reductive methylation of the aldehyde Ph 2 PfcCHO, with [Ph 2 P(CH 2 OH) 2 ]Cl, only led to the diphosphine Ph 2 PfcCH 2 N(Me)CH 2 PPh 2 ( 6 ). The diphosphine was structurally characterized and further reacted with [PdCl 2 (MeCN) 2 ] and [PdCl(Me)(cod)] (cod = η 2 :η 2 -cycloocta-1,5-diene), affording the respective trans -chelate complexes [PdCl(X){Ph 2 PfcCH 2 N(Me)CH 2 PPh 2 -κ 2 P , P ′}] ( 7a : X = Cl; 7b : X = Me), which were also structurally authenticated by X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

{[Tris(hydroxymethyl)methylamino]carbonyl}ferrocene ( 1 ) reacts with phosphorus(III) chloride in the presence of pyridine or triethylamine to afford a ferrocenyl-substituted bicyclic phosphite, {[(2,6,7-trioxa-1-phosphabicyclo[2.2.2]oct-4-yl)amino]carbonyl}ferrocene ( 2 ), in a moderate yield. (4,5-Dihydro-4,4-bis(chloromethyl)-2-oxazolyl)ferrocene ( 3 ) is found to be formed in some experiments as a minor side-product, resulting presumably via halogenation of 1 and base-induced cyclization of an intermediate chloromethyl derivative. The reaction of 2 with [W(CO) 4 (cod)] (cod = cycloocta-1,5-diene) at elevated temperature produces bis-phosphite complex cis -[W(CO) 4 ( 2 -κ P ) 2 ] ( 4 ) as the major product. All newly prepared compounds have been characterized by spectroscopic methods (IR, NMR and mass spectrometry) and elemental analysis. The crystal structures of 2 , 3 ·1/2H 2 O and 4 ·Me 2 CO·H 2 O were determined by single-crystal X-ray diffraction and the redox behaviour of phosphite 2 and the W(0) complex 4 was studied by cyclic voltammetry. [ABSTRACT FROM AUTHOR]