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Enantioselective hydrogenation of ketones is a key reaction in organic chemistry. In the past, we have attempted to deal with some unsolved challenges in this arena by introducing chiral tridentate phosphine-diamine/Ru catalysts. New catalysts and new applications are presented here, including the synthesis of phosphine-amino-alcohol P,N,OH ligands derived from (R,S)-1-amino-2-indanol, (S,S)-1-amino-2-indanol and a new chiral P,N,N ligand derived from (R, R)-1,2-diphenylethylenediamine. Ruthenium pre-catalysts of type [RuCl2(L)(DMSO)] were isolated and then examined in the hydrogenation of ketones. While the new P,N,OH ligand based catalysts are poor, the new P,N,N system gives up to 98% e.e. on substrates that do not react at all with most catalysts. A preliminary attempt at realising a new delta lactone synthesis by organocatalytic Michael addition between acetophenone and acrylonitrile, followed by asymmetric hydrogenation of the nitrile functionalised ketone is challenging in part due to the Michael addition chemistry, but also since Noyori pressure hydrogenation catalysts gave massively reduced reactivity relative to their performance for other acetophenone derivatives. The Ru phosphine-diamine system allowed quantitative conversion and around 50% e.e. The product can be converted into a delta lactone by treatment with KOH with complete retention of enantiomeric excess. This approach potentially offers access to this class of chiral molecules in three steps from the extremely cheap building blocks acrylonitrile and methyl-ketones; we encourage researchers to improve on our efforts in this potentially useful but currently flawed process. [ABSTRACT FROM AUTHOR]

Enantioselective transfer hydrogenation of benzofuranyl aryl ketones proceeds with moderate to good enantioselectivity even when the aryl group is not sterically differentiated by ortho-substituents. The best results are obtained with substrates that are functionalised by electron-withdrawing aryl groups that contrast with the electron-rich benzofuran, which is consistent with [Ru-ArC-H]˙Ar π interactions acting as a control element. Enantioselective pressure hydrogenation gives lower enantioselectivity irrespective of electronic effects, unless the aryl group is ortho-substituted, in which case up to 86% ee can be realised. [ABSTRACT FROM AUTHOR]

A convenient and chemoselective method for deoxygenation of pyridine N-oxide derivatives by transfer oxidation of triethylamine-catalysed by [Pd(OAc)2]/dppf is described. [ABSTRACT FROM AUTHOR]

Sum frequency generation (SFG) vibrational spectroscopy has been employed to study a variety of interesting biological phenomena occurring at interfaces. This review summarizes recent SFG studies on proteins, lipid monolayers and bilayers, and other biological molecules. Molecular level details revealed by SFG in these studies show that SFG is a powerful technique for characterizing conformation, orientation and ordering of biological molecules at interfaces. [ABSTRACT FROM AUTHOR]

A "polarization mapping" method has been applied to improve the fitting quality of sum frequency generation (SFG) vibrational spectra of complicated systems and validate the data analysis of simple SFG spectra. Using such a method, two-dimensional SFG spectra can be constructed, from which more reliable spectral information can be obtained from a surface/interface. Model calculations as well as experiments have been employed to illustrate the power of the polarization mapping method for spectral analysis of SFG spectra. By using a deuterated polystyrene surface and interfacial protein molecules as examples, we demonstrate that this method is especially important for complicated molecules, such as polymers and proteins. [ABSTRACT FROM AUTHOR]

A convenient synthesis of several ‘phosphomide’ ligands (P adjacent to carbonyl group) from secondary phosphines is reported. The new anisoyl substituted phosphines are considerable more stable to hydrolysis, and are stronger σ-donor ligands than P-acetyl-diphenylphosphine as determined by the measurement of ν(CO) for the corresponding rhodium carbonyl complexes trans-[RhL2(CO)Cl]. In contrast, a new phosphomide derived from perfluoro-octanoyl chloride was found to be a highly unstable, electron poor π-acceptor ligand. The crystal structure of [RhCp*Cl2{Ph2PC(O)CH3}] showed a normal pseudo-octahedral piano-stool molecular geometry with a Rh&z.sbnd;P bond length of 2.3186(5) A˚. The extra stability observed for the P-anisoyl phosphomides has led us to apply this class of ligand in rhodium catalysed hydroformylation for the first time. [Copyright &y& Elsevier]

The reaction of several tertiary amine functionalised phosphines with [Pt(COD)Cl2] has been studied. Reactions with ratios of L:Pt=2 proceeded cleanly to give either cis or trans complexes depending on the cone angle of the phosphines. The trans complexes could also be prepared by reaction with Zeise''s salt. Reactions of [Pt(COD)Cl2] with L:Pt=1 are less straightforward, and a mixture of cis and trans monodentate complexes, and in one example, a chelate complex have been isolated. The X-ray crystal structures of [PtCl2(η2-iPr2PN(Me)CH2CH2NMe2)] and a monodentate complex [trans-PtCl2(η1-iPr2PNH-c-NC5H10)2] are reported. [Copyright &y& Elsevier]

As part of a programme aimed at exploiting lignin as a chemical feedstock for less oxygenated fine chemicals, several catalytic C-C bond forming reactions utilising guaiacol imidazole sulfonate are demonstrated. These include the cross-coupling of a Grignard, a non-toxic cyanide source, a benzoxazole, and nitromethane. A modified Meyers reaction is used to accomplish a second constructive deoxygenation on a benzoxazole functionalised anisole. [ABSTRACT FROM AUTHOR]

Using the phospholane-phosphite ligand, BOBPHOS, almost perfect regioselectivities and high enantioselectivities (up to 92% ee) are observed in Rh catalysed enantioselective hydroformylation of vinyl arenes. This can be achieved under solvent-free conditions. [ABSTRACT FROM AUTHOR]

Ir complexes of chiral phosphine-diamine ligands catalyse the hydrogenation and transfer hydrogenation of aryl-piperidin-4-yl methanones, and ketones bearing both an aryl group and secondary alkyl substituent with up to 98% e.e., and with substrate to catalyst ratios of up to 4000. [ABSTRACT FROM AUTHOR]

Using a family of novel mononuclear and dinuclear palladium complexes of phanephos ligands, the simultaneous control of regioselectivity and enantioselectivity in the hydroxycarbonylation and alkoxycarbonylation of styrene derivatives has been realised for the first time. [ABSTRACT FROM AUTHOR]

Asymmetric hydrogenation of dibenzoyl-difluoro�methane has been studied for the first time. In contrast to �BINAL-H, baker’s yeast and CBS reduction procedures, ruthenium-catalysed hydrogenation using axially chiral diphosphine ligands provides excellent yield, diastereoselectivity and good enantioselectivity (up to 72% ee). Enantiomer enrichment by recrystallisation allows for the pure fluorinated diol to be isolated as a single enantiomer in moderate yield. [ABSTRACT FROM AUTHOR]

Rhodium catalysed hydroformylation of unsaturated esters has been studied. A pronounced temperature dependence was observed on the regioselectivity and catalytic activity for these reactions, and under the appropriate conditions, it is possible to obtain preferentially either linear or quaternary products. A quaternary selective hydroformylation of methyl atropate to give 1,3-aldehydic esters has also been developed. [Copyright &y& Elsevier]

Wiley‐VCH, Weinheim 2016. 2 Bände, 702 S., geb., 299.00 €.—ISBN 978‐3527335527 [ABSTRACT FROM AUTHOR]

Wiley‐VCH, Weinheim 2016. 2 volumes, 702 pp., hardcover, € 299.00.—ISBN 978‐3527335527 [ABSTRACT FROM AUTHOR]

Review: [40 refs. [ABSTRACT FROM AUTHOR]

Review: 36 refs. [ABSTRACT FROM AUTHOR]