Thiocyanate (SCN) adsorption on an Au electrode is examined using surface-enhanced Raman scattering (SERS) measurements, along with detailed density functional theory (DFT) calculations. Both the calculation and the spectroscopic measurements show that three different geometries are adopted by SCN adsorption in the potential region studied (0.0 V

The family of AZARYPHOS (aza–aryl–phosphane) phosphane ligands, containing a phosphine unit and sterically shielded nitrogen lone pairs in the ligand periphery, is introduced as a tool for developing ambifunctional catalysis by the metal center and nitrogen lone pairs in the ligand sphere. General synthetic strategies have been developed to synthesize over 25 examples of structurally diverse (6‐aryl‐2‐pyridyl)phosphanes (ARPYPHOS), (6‐alkyl‐2‐pyridyl)phosphanes (ALPYPHOS), 4,6‐disubsituted 1,3‐diazin‐2‐ylphosphanes or 1,3,5‐triazin‐2‐ylphosphanes, quinazolinylphosphanes, quinolinylphosphanes, and others. The scalable syntheses proceed in a few steps. The incorporation of AZARYPHOS ligands (L) into complexes [RuCp(L)2(MeCN)][PF6] (Cp=cyclopentadienyl) gives catalysts for the anti‐Markovnikov hydration of terminal alkynes of the highest known activities. Electronic and steric ligand effects modulate the reaction kinetics over a range of two orders of magnitude. These results highlight the importance of using structurally diverse ligand families in the process of developing cooperative ambifunctional catalysis by a metal and its ligand.

Bulky heterocycles: A highly selective catalytic cross‐coupling reaction of tertiary Grignard reagents with chloroazacycles provides a shortcut to heterocyclic building blocks for applications in pharmaceutical chemistry and supramolecular chemistry, or as ligand precursors in transition‐metal catalysis (see scheme).

The catalytic activity of [CpRu(L)(2)(MeCN)]PF(6) (L = 2-diphenylphosphinopyridine with bulky groups at C-6) for anti-Markovnikov hydration of terminal alkynes to aldehydes is retained when one heterocyclic ligand L is replaced by L' = PPh(3). Equal amounts of CpRuCl(PPh(3))(2) (1) and phosphane L in acetone solution equilibrate to a mixture of 1, CpRuCl(L)(PPh(3)) (2), and CpRuCl(L)(2) (3), which acts as highly active in situ catalyst for preparative anti-Markovnikov hydration of alkynes in water-rich media (2 mol % [Ru], 60 °C, 3-18 h in 4:1 (v/v) acetone/water). Reactions were completed in <15 min at 160 °C.

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O-Methylephedrine was identified as a very efficient chiral auxiliary for ortho-lithiation reactions of ferrocenes. (1R,2S)-O-Methylephedrine [CH(3)NHCH(CH(3))CH(Ph)OCH(3)] was reacted with N-ferrocenylmethyl-N,N,N-trimethylammonium iodide [FcCH(2)N(CH(3))(3)I; Fc = ferrocenyl] to give (1R,2S)-N-ferrocenylmethyl-O-methylephedrine. Treatment of this compound with t-BuLi in pentane followed by quenching with the electrophiles iodine, dibromotetrafluoroethane, chlorodiphenylphosphine or benzophenone gave 2-substituted ferrocenes in 98% de and with the (R(p))-ferrocene configuration. Subsequently, the chiral auxiliary could be replaced by systems including dimethylamine, acetate, diaryl- or dialkylphosphines to give a number of enantiopure bifunctional 1,2-disubstituted ferrocene derivatives such as (R(p))-N-2-iodo- or (R(p))-N-2-bromoferrocenylmethyldimethylamine or (R(p))-2-acetoxymethyl-1-diphenylphosphinoferrocene. As an application, ferrocenyl diphosphines possessing a planar (R(p))-ferrocene configuration only [1,2-(PPh(2))FcCH(2)PR(2), R = Cy, Ph, [3,5-(CF(3))(2)Ph]] were synthesized in three steps from O-methylephedrine and N-ferrocenylmethyl-N,N,N-trimethylammonium iodide in up to 77% overall yield.

Eleven novel aminophosphine ligands have been synthesized, all of which contain a chiral 2,2' '-bridged biferroceno unit as part of a biferrocenoazepine substructure. The efficiency of these compounds as chiral auxiliaries in palladium-mediated allylic substitution reactions has been investigated. Depending on the degree of (steric) fit between proper ligands and cyclic or noncyclic substrates, reactions with 46-87% ee were achieved. The molecular structure of a palladium dichloride complex of one of the ligands was determined by X-ray diffraction and compared to its binaphthyl analogue. In the solid state, the azepine substructure of these two complexes adopts totally different conformations with either local C(2) (binaphthyl) or local C(1) (biferrocene derivative) symmetry. These structural changes are well-reproduced by empirical force field calculations and are also reflected in significantly different behavior in asymmetric catalysis.

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