A novel Fe-NHC catalytic system allows the alkyl-alkyl cross-coupling reaction of alkyl halides and alkylmagnesium reagents has been developed. To our knowledge, this is the first Fe-catalysed Kumadatype coupling for the formation of C(sp 3 )-C(sp 3 ) bonds in the presence of functional groups. The process takes place under mild conditions, avoiding the formation of b-elimination products.Mechanistic studies suggest the intermediacy of Fe(I) complexes, formed by reduction with the Grignard reagent, as the active species.

A new catalytic system for the photooxidation of sulfides based on Pt(ii) complexes is presented. The catalyst is capable of oxidizing a large number of sulfides containing aryl, alkyl, allyl, benzyl, as well as more complex structures such as heterocycles and methionine amino acid, with complete chemoselectivity. In addition, the first sulfur oxidation in a continuous flow process has been developed.

Mit Erythrozyten als Templat lassen sich Polymeroberflächen prägen (siehe Rasterkraftmikroskopie‐Aufnahme). Trotz der hohen Flexibilität dieser Zellen zeigen die Abdrücke eine beträchtliche Selektivität für die verschiedenen Blutgruppen, wie aus den Sensorantworten mit der Quarzmikrowaage (Einschub) hervorgeht. So werden durch den Prägeprozess selektive synthetische Antikörper für die Erythrozytenantigene erzeugt.

A series of novel ligands based on N-heterocyclic carbene and sulfoxide functionalities have been prepared and characterized. Pd(II) complexes have been synthesized by transmetalation from the corresponding NHC−Ag derivatives, and their behavior as catalysts has been studied in arene C−H bond oxidative activation. Studies conducted toward the elucidation of the reaction mechanism of the acetoxylation suggest a C−H activation step at Pd(IV) rather than Pd(II) intermediates.

C'mon 1,2-dione: A new diastereo- and enantioselective Lewis base catalyzed domino Michael/aldol reaction converts alpha,beta-unsaturated aldehydes and 1,2-diones into chiral bicyclo[3.2.1]octane-6-carbaldehydes. The products are produced in good to excellent enantioselectivities (90-98 % ee) and can be transformed into bicyclic diols and triols. Additionally, a retro-aldol cyclization provides access to valuable tetrahydrochromenones (see scheme).

Enantiomerically enriched alpha,alpha-disubstituted phenylacetonitriles have been readily prepared by stereoselective quaternization of 2-alkyl-2-[2-(p-tolylsulfinyl)phenyl]acetonitriles with different alkylating electrophiles in the presence of bases. The use of potassium hexamethyldisilazane (KHMDS)/[18]crown-6 ether and NHMDS with alkyl halides afforded S,S(S) and R,S(S) diastereoisomers, respectively, in high enantiomeric purities, thus providing stereodivergent processes for synthesizing both isomers. The dependence of the stereochemical course of the reactions on the experimental conditions (mainly on the counterion) has been rationalized by assuming a planar or pyramidal structure for the benzylic carbanions. This hypothesis has been supported by NMR spectroscopic studies, which permit one to assign a chelated pyramidal structure to the sodium benzylic carbanions and an almost planar naked carbanionic structure to the potassium benzylic carbanions generated in the presence of [18]crown-6 ether.

Enantiomerically pure alpha-substituted alpha-amino phenylacetonitriles have been readily prepared from 2-p-tolylsulfinylbenzaldimines following a two-step sequence: a moderately stereoselective hydrocyanation of the imines and a completely stereoselective quaternization of the resulting diastereoisomeric mixture of alpha-amino phenylacetonitriles with different alkylating or acylating reagents in the presence of KHMDS. Theoretical calculations support a stereoselectivity control exerted by the remote sulfinyl group, as long as it is responsible for the conformational preferences of the benzyllithium intermediates, which suffer the attack of the electrophiles to the less hindered diastereotopic face.

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