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Abstract: Modification of material surfaces with polymers is an effective method to develop applicable polymer–material composites. Recently, multicomponent reactions (MCRs) have found their roles in advanced polymer chemistry and applied in surface modification. In this mini review, recent results of MCRs for surface modification are summarized, including the utilization of MCRs as coupling tools to link polymers on material surfaces, and polymers containing multicomponent structures for surface modification. The unique properties of these polymer–material composites stemming from MCRs are introduced, and the preliminary applications of these composites are also discussed. [ABSTRACT FROM AUTHOR]

One‐pot multicomponent reactions are very demanding in synthetic organic chemistry. Here we report a new polystyrene‐supported cerium catalyst (PS‐Ce‐amtp) obtained via an easy two‐step procedure, which was thoroughly characterized using various techniques. PS‐Ce‐amtp catalyses the environmentally benign one‐pot multicomponent synthesis of spiro‐piperidine derivatives through the reaction of substituted aniline, cyclic active methylene compound and formaldehyde at room temperature. The catalyst also exhibits excellent catalytic activity in one‐pot synthesis of 1,4‐disubstituted 1,2,3‐triazoles via click reaction between in situ generated azides (derived from anilines and amines) and terminal alkynes. The catalyst can be recovered easily after reaction and reused five times without significant loss in its catalytic activity. The advantageous features of this catalyst are atom economy, operational simplicity, short reaction times, easy handling and high recycling efficiency. [ABSTRACT FROM AUTHOR]

A greener synthesis of α-acyloxyamides was achieved by one-pot three component cascade Passerini reactions in a deep eutectic solvent (DES). Reactions proceeded rapidly and afforded the corresponding α-acyloxyamides by a variety of aldehydes, acids and isocyanides in excellent yields. The DES has the advantages of easy workup, high yield, and an environmentally benign and, moreover, shortened time as the greatest exclusivity of this system compared with previously reported methods. Graphical Abstract: Passerini three-component cascade reaction in a deep eutectic solvent: an environmentally benign and rapid system for the synthesis of α-acyloxyamides.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The sequential construction of diversified multifunctionalized thiazole derivatives through Pd-catalyzed regioselective C–H alkenylation has been accomplished. This versatile approach provides the diversified thiazole derivatives featuring orthogonal substitution patterns at the C-2, C-4 and C-5 positions from mono-substituted (2- or 4-substituted) thiazole derivatives or even more challenging simple thiazole. [ABSTRACT FROM AUTHOR]

A novel bridged pentacyclic skeleton has been constructed via the six-component domino reaction of glutaraldehyde, malononitrile, cyclic 1,3-dicarbonyl compounds and amines under microwave irradiation. In this one-pot transformation, 11 new bonds and five new rings have been formed. The main advantages of this protocol are short reaction time (within 30 min), practical simplicity, high regioselectivity, benign solvents, atom-economy, and environmental friendliness. [ABSTRACT FROM AUTHOR]

We have developed a procedure for the stereoselective and diastereodivergent synthesis of densely functionalised cyclohexanes containing four stereocentres through an asymmetric Michael-initiated ring closure (MIRC) cascade reaction employing hydrogen-bond catalysis, which is able to prepare adducts with different absolute configurations starting from the same starting materials. The overall process involves a highly diastereo- and enantioselective Michael/Henry cascade reaction between a wide range of nitroalkenes and α-nitro-δ-oxo esters, allowing access to different diastereoisomers of the final adduct by introducing subtle changes in the general ( R, R)-configured bifunctional tertiary amine/squaramide catalyst structure. Moreover, this methodology is also amenable to a three-component one-pot procedure, leading to the formation of the same adducts with very good results directly from commercially available reagents, on a multigram scale, and employing a very low catalyst loading. Furthermore, a detailed experimental and computational study is described which shows the origin of the diastereodivergent behaviour of these structurally similar catalysts and the nature of the substrate-catalyst interaction. [ABSTRACT FROM AUTHOR]

The first chiral catalyst for the three-component Ugi reaction was identified as a result of a screen of a large set of different BOROX catalysts. The BOROX catalysts were assembled in situ from a chiral biaryl ligand, an amine, water, BH3⋅SMe2 , and an alcohol or phenol. The catalyst screen included 13 different ligands, 12 amines, and 47 alcohols or phenols. The optimal catalyst system (LAP 8-5-47) provided α-amino amides from an aldehyde, a secondary amine, and an isonitrile with excellent asymmetric induction. The catalytically active species is proposed to be an ion pair that consists of the chiral boroxinate anion and an iminium cation. [ABSTRACT FROM AUTHOR]

A one-pot, consecutive, four-component synthesis of 5-acylpyrid-2-ones initiated by Pd/cataCXium® ABn catalysis proceeds under mild reaction conditions and in good yields, with a broad scope of three points of diversity. This sequence is superior to the initially proposed Pd/Cu-catalyzed version because all four components can be employed in close to stoichiometric amounts. [ABSTRACT FROM AUTHOR]

Simple and green synthetic procedures constitute an important goal in organic synthesis. The combination of multicomponent reactions (MCRs) and unconventional solvents has become a new research direction, which enables simultaneous growth of both MCRs and green solvents toward ideal organic synthesis. This review summarizes recent results of MCRs obtained in unconventional media including water, ionic liquids, polyethylene glycol and bio-based solvents. [ABSTRACT FROM AUTHOR]

The use of esters as blocking groups at the C2 position on a range of 3-substituted 5-membered ring heteroaromatics such as thiophenes or furans, allows control of the regioselectivity for the palladium-catalysed direct arylation at C5-H. This arylation can be followed by easy decarboxylation. This method allows sequential catalytic C5 arylation, decarboxylation and catalytic C2 arylation reactions. [ABSTRACT FROM AUTHOR]

An oxidative homo dimerization of N-protected and free indole derivatives toward bioactive 3,3′-linked biindolyl scaffolds viaPd-catalyzed direct C–H transformations was first successfully demonstrated. [ABSTRACT FROM AUTHOR]

Control over the monomer sequence during polymerization has attracted great attention in polymer science, but it remains a serious challenge. Recently, multicomponent reactions have been playing a significant role in the synthesis of sequence‐controlled polymers due to their inherent advantage of combining three or more starting materials in time‐saving, one‐pot operations to afford complex microstructures. In this feature article, the recent representative developments in the synthesis of sequence‐controlled polymers by multicomponent reactions are highlighted to give insight on the design of novel sequence‐controlled polymers with sufficient molecular diversity and complexity. The main part of this article is divided into three sections according to the different polymerization strategies using multicomponent reactions: direct multicomponent polymerization, multicomponent cascade polymerization, and iterative multicomponent reaction, respectively. It is anticipated that this feature article may provide some guidance for the fabrication of sequence‐controlled polymers by multicomponent reactions. Multicomponent reactions play a significant role in the synthesis of sequence‐controlled polymers due to their inherent advantage of combining three or more starting materials in time‐saving, one‐pot operations. The recent representative developments in the synthesis of sequence‐controlled polymers by multicomponent reactions are highlighted in this feature article to give insight on the design of sequence‐controlled polymers with sufficient molecular diversity and complexity. [ABSTRACT FROM AUTHOR]