The introduction of new noncovalent interactions to build functional systems is fundamental importance. We here report experimental and theoretical evidence that anion-π can contribute catalysis. Kemp elimination used as a classical tool discover conceptually innovative catalysts for reactions with anionic transition states. For catalysis, carboxylate base solubilizer are covalently attached the π-acidic surface naphthalenediimides. On these surfaces, transition-state stabilizations up ΔΔGTS...

Abstract magnified image Chiral macrocyclic tetra‐ and hexamine macrocycles derived from trans ‐1,2‐diaminocyclohexane (DACH) in complexes with diethylzinc efficiently catalyze the asymmetric hydrosilylation of aryl alkyl ketones enantiomeric excess product up to 89%. The cyclic structure trianglamine ligand increases enantioselectivity reaction, comparison catalysis acyclic N,N′ ‐dibenzyl‐DACH ligand. Density functional theory (DFT) computations on structures ligand‐zinc these a coordinated...

Chiral hexamine macrocycle derived from trans-1,2-diaminocyclohexane (DACH) in a complex with diethylzinc efficiently catalyzes the asymmetric hydrosilylation of N-phosphorylated aryl-alkyl or aryl-aryl ketimines protic media enantiomeric excess product approaching 100%. The cyclic structure trianglamine ligand increases enantioselectivity and/or yield reaction, comparison to catalysis by acyclic N,N′-dibenzyl-DACH ligands. Density functional theory (DFT) computations on model ligand-zinc...

The analysis of natural and artificial chiral compounds is vital wherever the nuances in three-dimensional structure are decisive for possibility their further use, e.g., as pharmaceuticals or catalysts. qualitative determination a entity requires either an anomalous scattering X-ray radiation chiroptical techniques, which electronic circular dichroism (ECD) one most useful. Chiroptical sensing that uses stereodynamic probes remains remedies problem lack suitable chromophore molecules...

Magnesium (Mg) constitutes one of the most abundant metal elements in Earth’s crust. The spectacular career magnesium organic chemistry has been initiated at beginning XX century and still lasting today. discovery organomagnesium compounds by Philippe A. Barbier Victor Grignard is commonly recognized as milestones development (organic) chemistry. subsequent applications reagents relatively easy generated synthons enantioselective reactions have opened new possibilities for acquiring...

Abstract NMR and ECD measurements together with density functional theory computations were used to analyze the mechanism of [Zn(diamine)(diol)]‐catalyzed ketone hydrosilylation. Of three possible pathways, one that assumes formation a Zn‐hydride species acting as an active catalyst appears energetically most favorable. This conclusion is in contrast previously proposed assumed reaction between [Zn(diamine)(diol)] catalyst, silane, substrate, took place through Zn‐activation carbonyl group....

Readily available chiral, triangular poly-azamacrocycles can act as receptors, low molecular weight supergelators and ligands in asymmetric synthesis.

Chiral acyclic and macrocyclic amines derived from trans-1,2-diaminocyclohexane in complexes with diethylzinc efficiently catalyze asymmetric hydrosilylation of aryl–alkyl aryl–aryl ketones enantiomeric excess the product up to 86 %. A trianglamine ligand a cyclic structure or presence an additional coordinating group increases enantioselectivity reaction, comparison catalysis by simple N,N′-dibenzyl-1,2-diaminocyclohexane ligand. In addition, effect activation catalyst variety alcohols...

Helicity induction in a highly flexible trityl chromophore is not only due to the presence of neighboring stereogenic center(s).

It has been found that ditrityl derivatives of (R,R)-N,N′-cyclohexane-1,2-diyldiacetamide and their analogues invariably form crystals possess inclusion properties. Enantiopurity is not a prerequisite for The molecules either two- or three-component compounds, in which hosts guests are connected by hydrogen bonds specific the included guest but always involving carbonyl groups host as acceptors. association mode undergoes certain changes depending on chemical modification molecule, type...

Ion mobility mass spectrometry and PM7 semiempirical calculations are effective complementary methods to study gas phase formation of noncovalent complexes from vaselike macrocycles. The specific association large-ring chiral hexaimines, derived enantiomerically pure trans-1,2-diaminocyclohexane various isophthaldehydes, is driven mostly by CH-π π-π stacking interactions. isotrianglimine macrocycles prone form two types aggregates: tail-to-tail head-to-head (capsule) dimers. stability the...

Chiral isotrianglimines were synthesized by the [3 + 3] cyclocondensation of (R,R)-1,2-diaminocyclohexane with C5-substituted isophthalaldehyde derivatives. The substituent's steric and electronic demands guest molecules' nature have affected conformation individual macrocycles their propensity to form supramolecular architectures. In crystal, formation a honeycomb-like packing arrangement simplest isotrianglimine was promoted presence toluene or para-xylene molecules. A less symmetrical...

Abstract New chiral derivatizing reagents (CDAs) derived from trans ‐1,2‐diaminocyclohexane, having an electron‐deficient aromatic substituent (either imide or 3,5‐dinitrobenzamide) and rigid structure amide a urea linker), are reported. Significant shift differences of diastereotopic protons in the 1 H NMR signals observed for enantiomers suitably protected α‐amino acids, linked to CDA by covalent bond. A simple, general model rationalizing enantiomer discrimination based on semiempirical...