Intermolecular annulation reactions of 1-aryl-2-naphthols with internal alkynes proceed efficiently in the presence of a Ru catalyst and a Cu oxidant to generate spirocyclic compounds by sequential cleavage of the C(sp(2))-H bond, migratory insertion of the alkyne, and dearomatization of the naphthyl ring. Various spirocyclic molecules bearing an all-carbon quaternary stereocenter could be obtained by this novel method with good yields and excellent regioselectivity, and the current process tolerates a variety of synthetically important functional groups.

A family of chiral C(2)-symmetric disulfoxide ligands possessing biaryl atropisomeric backbones has been synthesized by using the Andersen methodology. Complete characterization includes X-ray crystallographic studies of all ligands and some of their rhodium complexes. Their synthesis, optical purity, electronic properties, and catalytic behavior in the prototypical rhodium-catalyzed 1,4-addition of phenylboronic acid to 2-cyclohexen-1-one are presented through an in depth study of this ligand class. Density functional theory calculations on the step of the catalytic cycle that determines the enantioselectivity are presented and reinforce the first hypothetical explanations for the high levels of asymmetric induction observed.

A new class of easily accessible and stable imidazolin-2-ylidenes has been synthesized where the side chains are comprised of substituted naphthyl units. Introduction of the naphthyl groups generates C 2 -symmetric ( rac) and C s- symmetric ( meso) atropisomers, and interconversion between the isomers is studied in detail both experimentally and computationally. Complete characterization of the carbenes includes rare examples of crystallographically characterized saturated NHC structures. Steric properties of the ligands and an investigation of their stability are also presented. In catalysis, the new ligands show versatility comparable to the most widely used NHCs IMes/SIMes or IPr/SIPr. Excellent catalytic results are obtained when either the NHC salts (ring-opening alkylation of epoxides), NHC-modified palladium compounds (C-C and C-N cross-couplings), or NHC-ruthenium complexes (ring-closing metathesis, RCM) are employed. In several cases, this new ligand family provides catalytic systems of higher reactivity than that observed with previously reported NHC compounds.

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Molecular weaving: Mixing a CuII complex having a paddle‐wheel structure with a highly flexible neutral 1,3‐bis(4‐pyridyl)propane ligand (1:2 ratio) gives an interlaced braid which looks just like a hair plait (see X‐ray crystallographic structure). The three strands are held together through hydrogen‐bonding interactions.

Molecular braids represent one of the most fascinating topological networks in the fields of supramolecular chemistry and crystal engineering. In this Tutorial Review we provide an overview of the sustainable exploration of those metal-organic frameworks (MOFs) with the topology of molecular braid. Since the first example of the triple-stranded molecular braid in MOFs was reported by our group in 2005, another five attractive molecular braids in MOFs have already been prepared through several different pathways by us and other groups. Indeed, these known examples include the triple-, quintuple- and sextuple-stranded molecular braids. Besides the molecular braids found in MOFs, this type of unique topological network was also observed in organic co-crystals, and the only example of this is discussed in context as well.

Two saturated N-heterocyclic carbene ligands with substituted naphthyl side chains were used for the preparation of Blechert-type ruthenium metathesis precatalysts. The resulting conformers of the complexes were separated and unambiguously assigned by X-ray diffraction studies. All new complexes were compared in terms of activity to the original, SIMes-derived Blechert catalyst and were shown to be superior. A study on the impact of solvent concentration in RCM reactions using the most active of these new catalysts ultimately led to the ring closing of a variety of substrates at very low catalyst loadings.

From zero to hero? Sulfoxides are generally not considered useful ligand entities in asymmetric metal catalysis. However, a chiral disulfoxide as a chelating ligand in the rhodium-catalyzed 1,4-addition of aryl boronic acids to cyclic, alpha,beta-unsaturated ketones and esters gives impressive catalytic results, thus opening the door to future applications of this new chiral ligand class.