An Unexpected Construction of 2‐Arylquinolines from N‐Cinnamylanilines through sp3 C?H Aerobic Oxidation Induced by a Catalytic Radical Cation Salt

An unexpected reaction of cinnamylanilines was achieved through the radical cation salt‐induced aerobic oxidation of sp³ C H bonds, providing a series of 2‐arylquinolines. The mechanistic study shows that the cinnamylaniline was oxidized to an imine, which was attacked by the aniline generated through decomposition of the corresponding imine. After further intramolecular cyclization and aromatization, 2‐arylquinolines were obtained. This reaction provides a new method to construct 2‐arylquinolines from readily accessible starting materials.

     

Manganese(II)‐Mediated Domino Annulation Reaction of Vinyl Azides and 4‐Hydroxycoumarin: A Stereoselective Synthesis of Spirobenzofuranone‐lactams

A manganese(II) acetate‐catalyzed domino reaction of vinyl azides and 4‐hydroxycoumarin has been developed for the synthesis of polyfunctionalized spirofuranone‐lactams. A wide range of vinyl azides are capable of providing the desired spirofuranone‐lactams in good to excellent yields. The reaction was achieved via thermal decomposition of vinyl azides to 2H‐azirines, followed by an intramolecular nucleophilic attack and stereoselective cyclization. The mild reaction conditions and easy operation make this reaction advantageous for the synthesis of spirofuranone‐lactams.

     

Efficient Catalyst for Both Suzuki and Heck Cross‐Coupling Reactions: Synthesis and Catalytic Behaviour of Geometry‐ Constrained Iminopyridylpalladium Chlorides

A series of geometry‐constrained iminopyridyl‐palladium chlorides were synthesized and characterized. These phosphine‐free palladium complexes were explored for their catalytic activities in both Suzuki and Heck cross‐coupling reactions, achieving turnover numbers as high as 10⁶ towards various aryl bromides, even those containing various functionalities. In addition, the influence of substituents with steric and electronic factors was reflected by the differences observed in their activities.

     

Enantioselective One‐Pot Reaction: Organocatalyzed Synthesis of Fully Functionalized Oxabicyclo[2.2.2]octanes with Seven Contiguous Stereocenters

An enantioselective one‐pot Michael/Michael/Henry/hemiacetalization reaction between α,β‐unsaturated aldehydes, α‐ketoamides, and nitroalkenes under mild conditions catalyzed by a diarylprolinol silyl ether has been developed. The sequential methodology provides a direct approach to a wide range of fully substituted chiral oxabicyclo[2.2.2]octanes with seven contiguous stereocenters in moderate to excellent yields (up to 99%), high to excellent diastereoselectivities (up to >25:1 dr), and high to excellent enantioselectivities (up to 99% ee).

     

Enhanced mechanical,thermal and dielectric properties of polyimide nanocomposites containing SiCp (SiCw) nanofillers for high energy-storage applications

Journal of Polymer Research - In this paper, we aimed to develop the nanocarrier based on poly (N-isopropyl acrylamide)—allyl acetoacetate grafted MoS2 nanosheets. The obtained polymer...     

Influences of internal erosion on infiltration and slope stability

Bulletin of Engineering Geology and the Environment - Rainfall-induced slope failures in natural terrains are destructive natural disasters. Transport of fine particles may be induced by the...     

对高层房屋建筑施工技术的分析与思考

我国的高层房屋不断改进内部与外部技术,内蒙古乌兰察布市兴和县也随之向着秩序化、多功能化、智能化等方面发展。在高层房屋的施工技术问题方面,只有提升技术水平才能够适应现代化的施工技术。本文以高层房屋建筑施工技术为基本点,进行详细的分析与思考。