Applicability and productivity of new click chemistry that exploits a nitrile N-oxide as 1,3-dipole in polymer synthesis were demonstrated by the polymerization diynes with homo ditopic aromatic N-oxide. The was synthesized situ reaction corresponding hydroxamoyl chloride molecular sieves 4 Å. various efficiently produced polyisoxazoles high yields. also useful for connection bisacetylene-terminated polymers to give multiblock copolymers very yield. resulting agree well structural assignment...

Abstract Effective induction of preferred‐handed helicity polyacetylenes by pendant mechanically chiral rotaxanes is discussed. Polyacetylenes possessing optically active in the side chains were synthesized polymerization corresponding enantiopure [2]rotaxane‐type ethynyl monomers prepared chiral‐phase HPLC separations. The CD Cotton effects revealed that took helical conformations depending on rotaxane chirality. helix was not disturbed an additional substituent chain. These results...

The activities of liver drug-metabolising enzymes for 16 aromatic or chlorinated hydrocarbons were measured in male rats after a three-week daily intake ethanol amounting to 30% total energy intake. Although the feeding produced only slight increase microsomal cytochrome P-450 content, it increased in-vitro metabolism most three-to six-fold. That major part this enhanced activity disappeared one-day withdrawal suggests that recent plays an important accelerating hydrocarbons. enzyme by was...

Main-chain-type poly[2]rotaxanes (9 and 12) poly[3]rotaxanes (10 13) were synthesized by a new click polymerization using unstable stable homoditopic nitrile N-oxides according to rotaxanation protocol. Rotaxane monomers prepared from ethynyl-functionalized crown ether sec-ammonium salt via the typical urethane end-capping The N-oxide 8′ was generated in situ through reaction of corresponding hydroxamoyl chloride 8 with molecular sieves 4 Å. diethynyl-functionalized [2]rotaxane 5 [3]rotaxane...

Linear-cyclic polymer structural transformation and its reversibility are demonstrated by a simple but rational strategy using the characteristics of crown ether-based rotaxanes. The structure containing [1]rotaxane unit at one end was controlled conventional protection-deprotection reactions, giving rise to reversible linear-cyclic transformation.

Rotaxane-structure-specific Pd-catalyzed rearrangement of propargyl or allyl urethane groups to oxazolidinone moieties proceeded efficiently. The conversion took place successively by the translation wheel along axle, thus providing a novel macrocyclic catalytic system.

Polyrotaxane networks were synthesized from a mixture of poly(crown ether)s (2−5) as trunk polymer and dumbbell-shaped bifunctional secondary ammonium salt 6 bearing disulfide linkage bulky end caps cross-linking agent in the presence catalytic amount benzenethiol via reversible thiol−disulfide interchange reaction. Trunk polymers 2−4 prepared by copolymerization bis(hydroxymethyl)dibenzo-24-crown-8-ether 1 comonomers. Poly(crown ether) 5 poly(tetrahydrofuran) (PTHF) spacer was also PTHF...

Polyacetylene bearing a pendant rotaxane moiety with an optically active wheel component was synthesized to realize reversible structural control of its helical structure by position the component. formed one-handed only when moved close main chain.

A click end-capping reaction exploiting nitrile N-oxide to rotaxane was described with emphasis of productivity the protocol via stable C-C bond formation. Establishment a pH-driven molecular shuttling system also demonstrated by practical neutralization sec-ammonium group axle potassium hydroxide.

We achieved a highly efficient one-pot synthesis of permethylated α-cyclodextrin(CD)-based polyrotaxane via an initial complexation to the inclusion complex with amine-terminated polytetrahydrofuran followed by end-capping bulky isocyanate in hydrocarbon solvent under heterogeneous conditions. Among various organic solvents tested, isooctane was best solvent, while cyclohexane yielded no polyrotaxane. Effects reaction temperature, molecular weight axle polymer, structures wheel and...

A thermoresponsive rotaxane shuttling system was developed with a trichloroacetate counteranion of an ammonium/crown ether-type rotaxane. Chemoselective thermal decomposition the ammonium moiety on yielded corresponding nonionic accompanied by positional change crown ether axle. The skeleton facilitated effective dissociation acid, markedly lowering temperature.

Abstract Directed helicity control of a polyacetylene dynamic helix was achieved by hybridization with rotaxane skeleton placed on the side chain. Rotaxane‐tethering phenylacetylene monomers were synthesized in good yields ester end‐capping pseudorotaxanes that consisted optically active crown ethers and sec ‐ammonium salts an ethynyl benzoic acid. The polymerized [{RhCl(nbd)} 2 ] (nbd=norbornadiene) to give corresponding polyacetylenes high yields. Polymers wheel components are far from...

Abstract A supramolecular cross‐linked cross‐linker, capable of introducing rotaxane cross‐links to vinyl polymers, has been developed for the rational synthesis polyrotaxane networks. The experimental results reveal that combination an oligocyclodextrin (OCD) and a terminal bulky group‐tethering macromonomer (TBM) forms polymer‐network structure having polymerizable moieties through cross‐linking. Radical polymerization variety typical monomers in presence vinylic cross‐linker (VSC)...

A catalyst- and solvent-free synthesis of cyclodextrin-based polyrotaxanes exploiting a stable nitrile N-oxide as an end-capping agent was achieved. The C-C bond-forming reaction allyl-terminated pseudopolyrotaxane with the proceeded smoothly by solid-state grinding in mortar to afford polyrotaxane.

The synthesis and structure of graft polyrotaxane, a novel class copolymer possessing mobile chains, is described. Poly(tetrahydrofuran) was bound to the axle components pseudo[2]rotaxane as chain by grafting-onto method afford corresponding polyrotaxane (see picture). N-Acetylation ammonium moieties lead an increase in dynamic radius polyrotaxane. Detailed facts importance specialist readers are published "Supporting Information". Such documents peer-reviewed, but not copy-edited or...

An α-cyclodextrin-based size-complementary [3]rotaxane with an alkylene axle was selectively synthesized in one pot via end-capping reaction 2-bromophenyl isocyanate water. Thermal degradation of the product yielded not only original components but also [2]rotaxane. Thermodynamic studies suggested a stepwise deslippage process.

The effect of rotaxane shuttling on the fluorescence properties a fluorophore was investigated by exploiting fluorophore-tethered [2]rotaxanes. A fluorescent boron enaminoketonate (BEK) moiety introduced in via transformation an isoxazole unit generated as result end-capping reaction using nitrile N-oxide. exhibited red shift maximum along with remarkable enhancement quantum yield through wheel translation to fluorophore.

Configuration confirmed: The first total synthesis and structure assignment of the anthrone C-glycoside cassialoin (1) have been achieved by exploiting an isoxazole-containing stereogenic α-ketol a subsequent intramolecular redox reaction (see retrosynthetic analysis; MOM = methoxymethyl).

Intramolecular 1,3-dipolar cycloaddition of 2-phenoxybenzonitrile N-oxides to benzene rings, accompanied by dearomatization, formed the corresponding isoxazolines in high yields. The X-ray single-crystal structure analysis revealed that reaction cis-adduct as a single isomer. substituents on rings markedly affected rate, yield, and final product.

Macromolecular [2]rotaxanes, which consist of a polymer chain threading into wheel component, were synthesized in high yield and with purity. The synthesis was achieved by the ring-opening polymerization (ROP) δ-valerolactone (VL) using hydroxyl-terminated pseudorotaxane as an initiator diphenyl phosphate catalyst dichloromethane at room temperature. 1H NMR, gel permeation chromatography (GPC), MALDI-TOF-MS measurements resulting poly(δ-valerolactone)s clearly indicate presence rotaxane...