A general, practical, and efficient synthesis of <italic>N</italic>,<italic>N</italic>′-disubstituted sulfamides has been developed applied to the preparation polysulfamides, a virtually unknown class polymers.

A new gold(I)-catalyzed cycloisomerization to access highly substituted piperidines has been developed. By combining a conceptually way of generating iminium ions using cationic gold(I) complexes and an efficient cyclization reaction that can minimize potentially competing aza-Cope rearrangement, the proposed successfully circumvents long-standing problem in classical aza-Prins reaction. Synthetic utility catalytic was demonstrated by synthesis optically active 2-alkyl-piperidin-4-one.

Carbon–carbon bond formation by [3,3]-sigmatropic rearrangement is a fundamental and powerful method that has been used to build organic molecules for long time. Initially, Claisen Cope rearrangements proceeded at high temperatures with limited scopes. By introducing catalytic systems, highly functionalized substrates have become accessible forming complex structures under mild conditions, asymmetric synthesis can be achieved using chiral systems. This review describes recent breakthroughs...

Abstract Poly(2‐isopropyl‐2‐oxazoline) ( P i PrOx ) is a biocompatible polymer with temperature‐sensitive behavior that exhibits hydrophilic‐hydrophobic phase transition in response to temperature changes via lower critical solution (LCST). Typically, the LCST of s significantly depending on their molecular weight or concentration. In this study, bottlebrush polymers PrOx‐BP s) are created using cascade enyne metathesis polymerization ‐based macromonomer. The unique shape s, densely packed...

Poly(p-phenylenevinylene)s (PPVs), a staple of the conductive polymer family, consist alternating alkene and phenyl groups in conjugation. The physical properties this organic material are intimately linked to cis/trans configuration groups. While many synthetic methods afford PPVs with all-trans stereochemistry, very few deliver all-cis congeners. We report herein synthesis living characteristics via stereoretentive ring-opening metathesis polymerization (ROMP). Exquisite catalyst control...

α-Functionalization of carbonyl compounds in organic synthesis has traditionally been accomplished via classical enolate chemistry. As α-functionalized moieties are ubiquitous biologically and pharmaceutically valuable molecules, catalytic α-alkylations have extensively studied, yielding a plethora practical efficient methodologies. Moreover, stereoselective carbon–carbon bond formation at the α-position achiral achieved by using various transition metal–chiral ligand complexes. This review...

A stereocontrolled degradable polymer was synthesized via living cascade enyne metathesis polymerization. Highly stereodefined N,O-acetal-containing monomers were prepared using the Pd-catalyzed hydroamination of alkoxyallenes and ring-closing metathesis. The resulting chiral exhibited a narrow dispersity window. Block copolymers not only by sequentially adding nondegradable but also enantiomerically different to produce blocks. Owing hydrolyzable N,O-acetal moiety in backbone structure,...

The first gold-catalyzed intermolecular coupling of alkynoates and allylic ethers invoking alkoxy addition [3,3]-sigmatropic rearrangement as the key mechanism has been developed. Remarkably, reaction showed complete chemoselectivity toward pathway initiated by to alkynes. This unprecedented reactivity led a new access diversely substituted β-alkoxyacrylates in highly efficient manner.

An efficient synthesis of the tricyclic cyclopenta[1,2-b]pyrrolo[1,2-a]azepine nucleus stemonamine alkaloids is reported. The key reaction utilizes a one-pot gold(I)-catalyzed cyclization and SnCl4-mediated Schmidt rearrangement. Notably, phosphine ligand had crucial effect on cyclization. As an application this new methodology, formal (±)-stemonamine has been accomplished.

A highly removable N-heterocyclic carbene ligand for a transition-metal catalyst in aqueous media via host–guest interactions has been developed. Water-soluble adamantyl tethered ethylene glycol the leads hydrophobic inclusion into cavity of β-cyclodextrin. Ruthenium (Ru) olefin metathesis with this demonstrated excellent performance various reactions water as well CH2Cl2, and removal residual Ru was performed filtration utilizing interaction extraction.

A glucose-based bioadhesive has been synthesized by radical polymerization. The adhesion was significantly enhanced biologically safe SPAAC crosslinking after initial attachment on a substrate.

A photodegradable nitrophenylene polymer was prepared via ring-opening metathesis polymerization (ROMP). The resulting degraded in the presence of UVA light without any chemical additives within 1 hour.

A study of reaction kinetics and removal efficiency a family ruthenium (Ru)-based olefin metathesis catalysts containing ethylene-glycol-oligomer-tethered N-heterocyclic carbene (NHC) ligands has been carried out, with focus on variation ethylene glycol oligomer length. The length was precisely defined by sequential addition repeating units. Due to the dual solubility oligomer, produced catalyst highly soluble in both aqueous organic solvents (dichloromethane). In solution, polarity increase...

A covalent connection between two orthogonal functional groups (-NH2 and -OH) in metal-organic frameworks (MOFs) has been developed. This post-synthetic ligand cyclization (PSLC) was successfully demonstrated to synthesize a benzoxazole-functionalized MOF from Zr-based UiO-66-2,3-(NH2)(OH) under microwave irradiation. In contrast, the regioisomeric UiO-66-2,5-(NH2)(OH) only produces non-cyclized formamide-functionalized MOF.

Abstract A degradable acetal‐backboned polymer was developed via palladium‐catalyzed hydroalkoxylation of dialkoxyallenes with diols. Dialkoxyallenes were easily prepared from the corresponding diols through propargylation, followed by isomerization. Polymers synthesized various combinations and dialkoxyallens in presence a palladium catalyst to produce acrolein acetal linkages. While backbones completely degraded into diols, recycling 1,4‐benzenedimethanol also demonstrated. The vinyl...

Silver carbonate (Ag2CO3), a common transition metal-based inorganic carbonate, is widely utilized in palladium-catalyzed C–H activations as an oxidant the redox cycle. can also act external base reaction medium, especially organic solvents with acidic protons. Its superior alkynophilicity and basicity make silver ideal catalyst for reactions alkynes, carboxylic acids, related compounds. This review describes recent reports of carbonate-catalyzed carbonate-mediated transformations, including...

Several biological macromolecules adopt bivalent or multivalent interactions to perform various cellular processes. In this regard, the development of molecular constructs presenting multiple ligands in a specific manner is becoming crucial for understanding and detection target macromolecules. Nucleic acids are attractive molecules achieve goal because they capable forming various, structurally well-defined 2D 3D nanostructures can bear on their structures with precisely controlled...

1 10 AgSbF6 (10) rt 20 h 40% 2 AgBF4 22 3 AgOTf 4 55% 0 C 81% isolated yield after two-step conversion. 1d was in 15% yield. 7% Developing new methodologies for the synthesis of piperidines have been attracting interest synthetic chemists. Recently, we reported gold(I)-catalyzed cycloisomerization N,O-mixed acetals generated from homopropargylic amines, which led to a unique approach highly substitutued piperidin-4-ones. A key aspect this reaction is chemoselective activation alkynes (path...

Positively charged aromatic and aliphatic quaternary ammonium groups were successfully installed in metal–organic frameworks (MOFs) through post-synthetic modification (PSM) exchange (PSE) for hydroxide conductivity studies.

Abstract Herein, air‐stable poly(benzonorbornadiene) was synthesized via ring‐opening metathesis polymerization. Conventional easily decomposed in the presence of molecular oxygen owing to generation radicals at allylic and benzylic hydrogens. However, our sterically bulky aryl‐group substituents polymers physically blocked access these positions. The resulting preserved their backbones for more than 2 weeks air. Postmodification bromophenyl‐substituted polymer successfully afforded expanded...

An alternative approach for controlling the polymer molecular weight distribution (MWD) was developed based on degradation of precisely synthesized degradable long-chain polymers.

Piperidine is one of the most common building blocks alkaloids. For this reason, there have been great efforts to develop new synthetic methods for piperidine structures. Recently, we developed a unique approach highly substituted piperidin-4-ones, using gold(I)-catalyzed cycloisomerization mixed N,O-acetals derived from homopropargylic amines. In progress applying method total synthesis natural alkaloids, special attention was given bicyclic indolizidine and quinolizidine structures, which...