The University of Osaka · 화학
나오후아 칸바야시 교수의 연구실은 희토류 금속 촉매를 활용한 고선택성 유기합성 반응, 특히 플레너-키랄 사이클로펜타디엔일 루테늄 촉매를 통한 비대칭 알릴화 반응과 고분자 합성 기반의 분자 설계를 핵심으로 합니다. 특히 π-π 상호작용에 기반한 안정한 π-스택드 고분자 구조를 설계하고, 아미노산 衍생기를 도입하여 분자 내 수소결합을 유도함으로써 열적 안정성이 높은 헬리컬 고분자를 개발하고 있습니다. 이는 분자전자소자 및 고성능 고분자 재료의 개발에 기여할 잠재력을 지닙니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
An asymmetric allylic substitution with sodium carboxylate using a planar-chiral cyclopentadienyl ruthenium complex has been developed. Optically active allylic esters were prepared in good yields with high regio- and enantioselectivities.
Abstract We report the asymmetric allylic alkylation of allylic chlorides with silyl enolates as a carbon nucleophile using a planar‐chiral cyclopentadienyl‐ruthenium (Cp′Ru) catalyst. The reaction proceeds under unusually mild conditions to give the desired branched products with complete regioselectivity and high enantioselectivity, and reactive functional groups, such as aldehyde, can be tolerated. In this reaction system, Cp′Ru plays an important role in activating both silyl enolate and all
Living cyclocopolymerization through the alternating insertion of an isocyanide and allene into palladium-carbon bond was developed based on the controlling the reactivity of the propagation species using bidentate ligands. We revealed that the rate of the presented cyclocopolymerization was depended on the ligands of Pd-initiator. When the palladium-methyl complexes having appropriate cis-chelating ligand, such as 1,3-bis(diphenylphosphino)propane (dppp), were used as initiator, the cyclocopoly
π-Stacked polymers, which consist of layered π-electron systems in a polymer, can be expected to be used in molecular electronic devices. However, the construction of a stable π-stacked structure in a polymer is considerably challenging because it requires sophisticated designs and precise synthetic methods. Herein, we present a novel π-stacked architecture based on poly(quinolylene-2,3-methylene) bearing alanine derivatives as the side chain, obtained through the living cyclo-copolymerization o
Molecular design involving the incorporation of an α-amino acid residue into the side chain or main chain of a polymer is often used to stabilize artificial molecular architectures through intramolecular hydrogen bonding. However, this molecular design strategy rarely considers the importance of interactions between substituents at the α-position of amino acid moieties, as found in nature. Herein, we report the synthesis of a novel series of π-stacked helical poly(quinolylene-2,3-methylene) with
Ru zeigt, was es kann: Eine asymmetrische Auto-Tandemreaktion mit einem planar-chiralen Cyclopentadienyl-Ruthenium-Komplex als Katalysator verbindet Allylchloride und α-Halogenamide zu nützlichen diastereomeren- und enantiomerenangereicherten γ-Lactamen mit mehreren Stereozentren. Die Umsetzung verläuft als Eintopfsequenz aus allylischer Amidierung und radikalischer Atomtransfercyclisierung. PG=Schutzgruppe.
A new type of asymmetric polymerization reaction by asymmetric allylic substitution catalyzed by planar-chiral cyclopentadienyl-ruthenium (Cp′Ru) complexes is described. Achiral AB-type monomers, which feature both the allylic chloride and N-alkoxyamide moieties in a single molecule, are smoothly polymerized by the catalysis of chiral ruthenium complexes with quantitative monomer conversion to afford optically active polyamides in good yields. The resulting polymers are characterized by optical
Weniger ist mehr: Ein neuer Zugang zu chiralen Allylalkoholen nutzt die regio- und enantioselektive Substitutionsreaktion monosubstituierter Allylchloride mit Wasser. Die Reaktion wird von planar-chiralen Cyclopentadienylrutheniumkomplexen effizient katalysiert (siehe Schema). Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please no
ABSTRACT We, herein, present a novel synthesis of responsive helical poly(aryl isocyanide)s bearing aza‐crown ethers as pendant groups. Chiral aryl isocyanide monomers bearing an aza‐crown ether as a pendant were designed and synthesized, piror to polymerization using a Pd‐Pt µ‐ethynediyl complex as an initiator to give the corresponding polymers in good yield. The resulting polyisocyanides adopted a stable helical structure in solution, as confirmed by circular dichroism spectroscopic analysis.
A new mode of polymerization has been developed that involves the alternating heteroinsertion of isocyanide and allene. Aryl isocyanides that contain both isocyano and allenyl moieties were designed and synthesized. The molecules rapidly polymerized in the presence of [bis(triphenylphosphino)methyl]palladium chloride through the fully alternating insertions of the isocyanide and allene moieties into a palladium–carbon bond to afford novel polymers that contain quinoline backbones. The polymer ch
In this study, we examined novel synthetic methods for optically active polymers bearing various side chains from post-polymerization modification of a single optically active polymer.
A new synthetic approach for optically active polymer-bearing chiral cyclic architecture is described. The polymer is prepared by a combination of asymmetric allylic amidation catalyzed by planar-chiral ruthenium (Cp′Ru) complexes and ring-closing metathesis (RCM) reaction. We have designed bifunctional monomers bearing allylic chloride and N-alkoxyamide possessing an olefinic moiety, and the resulting polymer provides two olefinic moieties for RCM reactions in each monomer unit. These monomers
The first polymerization system based on the alternating insertion of an isocyanide and alkyne into palladium–carbon bonds has been developed.
The facile synthesis of end-functionalized poly(quinolylene-2,3-methylene)s using aryl palladium initiators conveniently prepared from versatile aryl halides has been reported. When various aryl palladium complexes with 1,3-bis(diphenylphosphino)propane, synthesized by the oxidative addition of an aryl halide to Pd(PPh3)4 and the ligand exchange reaction, were used as initiators, cyclocopolymerization of o-allenyl aryl isocyanide afforded poly(quinolylene-2,3-methylene)s with a narrow molecular
In this study, we examined the regio-, diastereo-, and enantioselective polymerization using asymmetric allylic alkylation catalyzed by a planar-chiral cyclopentadienyl-ruthenium (Cp′Ru) complex ((<italic>S</italic>)-<bold>1</bold>).
