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A mild methodology is developed for the synthesis of a range of fused bicyclic lactone-pyrrolidinones.

The key step of the 10-step synthesis of the marine alkaloid (-)-(I) is an asymmetric Mannich-type reaction.

The regioselectivity of the palladium-catalyzed cyclization of propargylic carbonates with sulfonamide nucleophiles is critically dependent on the bite angle of the bidentate phosphine ligand. Ligands with small bite angles favor attack on the central carbon atom of an allenylpalladium intermediate to afford cyclic dienamide products, whereas the use of those with large bite angles leads to alkynyl azacycles, with high stereoselectivity. A computational analysis of the reaction pathway is also presented.

Tryptamine-derived ureas undergo Michael addition/iminium ion cyclization reaction upon treatment with enones in the presence of a chiral BINOL derived phosphonic acid catalyst to give polyheterocyclic products with good enantioselectivities.

Treatment of the azetidinol (I) with sBuLi followed by reaction with various electrophiles results in stereoselective formation of 2,3-trans-substituted derivatives with exception of CD3OD which predominantly yields the cis-product.

Substituted pyrrolidines are synthesized by ring closure initiated by direct nucleophilic attack of stabilized enolates at the nitrogen of oximes (I), (IV), (VII) and (IX) activated with an appropriate leaving group.

Various 3-fluoropyrrolidines and 4-fluoropyrrolidin-2-ones were prepared by 5-exo-trig iodocyclisation from allylic fluorides bearing a pending nitrogen nucleophile. These bench-stable precursors were made accessible upon electrophilic fluorination of the corresponding allylsilanes. The presence of the allylic fluorine substituent induces syn-stereocontrol upon iodocyclisation with diastereomeric ratios ranging from 10:1 to > 20:1 for all N-tosyl-3-fluoropent-4-en-1-amines and amides. The sense and level of stereocontrol is strikingly similar to the corresponding iodocyclisation of structurally related allylic fluorides bearing pending oxygen nucleophiles. These results suggest that the syn selectivity observed upon ring closure involves I(2)-π complexes with the fluorine positioned inside.

The optimized Rh(I)-catalyzed reaction of aryl methyl sulfides such as (I) with terminal alkynes affords arylvinyl methyl sulfides.

Cyclic and acyclic propargylic carbonates undergo unusual palladium-catalyzed cyclization reactions to give 2-alkynyl oxacycles.

Two different halogenation procedures including both (DHQ)2-PHAL as the enantioselective agent are developed for the preparation of fluorinated heterocyclic scaffolds which are obtained as exclusive cis isomers.

[K(2,2,2-crypt)]3[Mn@Pb12]·1.5en is synthesized by addition of a solution of Mn3(Mst)6 in THF to a mixture of K4Pb9 and 2,2,2-crypt dissolved in en.

It's all in the ligand: By choice of the appropriate diphosphine ligand a previously linear-selective alkyne hydroacylation process can be "switched" to be highly branched-selective (see scheme, l=linear, b=branched). Structural data for the ortho-iPr-dppe-rhodium catalyst suggest restricted rotation of the phosphine aryl units may be responsible for the observed selectivity. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The structures of (IIIa) (monoclinic, space group P21/c, Z = 4) and (IIIb) (monoclinic, P2/n, Z = 4) are determined by single crystal XRD.

The Rh-catalyzed asymmetric addition of α- (VII) or β-substituted S-chelating aldehydes (I), (V) towards terminal alkynes (II) is successfully used as kinetic resolution procedure to afford the corresponding α- and β-substituted enones in up to 90% optical purity.

The first examples of amide-tethered aminohydroxylation reactions, catalyzed by osmium, showing that the use of N−O-based reoxidants are essential for success, are reported. The system that is described is compatible with a variety of different alkene substitution patterns and ring sizes and works with low loadings in both cyclic and acyclic systems. The levels of diastereoselectivity that were observed for substituents at both the allylic and homallylic position bode well for the use of stereoselective TA reactions in organic synthesis.

RCM can be used to make aromatic heterocycles, namely pyridines and, for the first time, pyridazines; the key step after RCM involves elimination of sulfinate to provide the aromatic system.

Advances in hardware and software have made X-ray crystallography even more attractive as the first-option method for structure analysis. For most organic materials containing up to 100 non-hydrogen atoms, getting from the initial visual examination of the sample to producing publication-ready tables and pictures should usually be achievable in a single morning. Improvements in hardware have also increased reliability of the determination of absolute configuration. A recently published new algorithm may extend the range of applicability of the method.