Surface-Initiated Ring-Opening Metathesis Polymerization (SI-ROMP): History, General Features, and Applications in Surface Engineering with Polymer Brushes

Surface-Initiated Ring-Opening Metathesis Polymerization (SI-ROMP) has attracted great attention in the past two decades because of its high efficiency in decorating material surfaces with functional polymer brushes. To fill the vacancy of review articles in SI-ROMP, this article is aimed at giving an overview of the history, the general features and procedures, and applications of SI-ROMP, guiding future researchers in this field. In general, SI-ROMP consists of three main steps: surface functionalization with olefin anchors, attachment of catalyst to the surface, and polymerization from the surface. Several metal-based catalysts for ROMP in solution have been developed, but most SI-ROMP reactions use the ruthenium-based Grubbs catalysts. SI-ROMP enables the rapid growth of polymer films on a large variety of substrates such as silica, gold, graphene oxides, carbon nanotubes, metal oxide nanowires, and composite polymer membranes. There are many methods to characterize these polymer brushes. In addition, some novel techniques have been developed to precisely control the surface polymer growth and lead to polymer films with unique structures and functions. Up to this day, SI-ROMP can be applied to the surface engineering of many novel materials, including ultrahydrophobic surfaces, microfluidic channels, electric devices, ion exchange media, and responsive surfaces.

Highly efficient Ru(ii)–alkylidene based Hoveyda–Grubbs catalysts for ring-closing metathesis reactions

Three novel phosphine-free Ru-alkylidenes (7a–7c) have been synthesized and utilized as efficient catalysts for ring closing metathesis (RCM) reaction.

Dehydrogenative alcohol coupling and one-pot cross metathesis/dehydrogenative coupling reactions of alcohols using Hoveyda-Grubbs catalysts

In this study, in-situ formed ruthenium hydride species that were generated from Grubbs type catalyst are used as efficient catalysts for dehydrogenative alcohol coupling and sequential cross-metathesis/dehydrogenative coupling reactions. The...

Application of New Efficient Hoveyda–Grubbs Catalysts Comprising an N→Ru Coordinate Bond in a Six-Membered Ring for the Synthesis of Natural Product-Like Cyclopenta[b]furo[2,3-c]pyrroles

The ring rearrangement metathesis (RRM) of a trans-cis diastereomer mixture of methyl 3-allyl-3a,6-epoxyisoindole-7-carboxylates derived from cheap, accessible and renewable furan-based precursors in the presence of a new class of Hoveyda–Grubbs-type catalysts, comprising an N→Ru coordinate bond in a six-membered ring, results in the difficult-to-obtain natural product-like cyclopenta[b]furo[2,3-c]pyrroles. In this process, only one diastereomer with a trans-arrangement of the 3-allyl fragment relative to the 3a,6-epoxy bridge enters into the rearrangement, while the cis-isomers polymerize almost completely under the same conditions. The tested catalysts are active in the temperature range from 60 to 120 °C at a concentration of 0.5 mol % and provide better yields of the target tricycles compared to the most popular commercially available second-generation Hoveyda–Grubbs catalyst. The diastereoselectivity of the intramolecular Diels–Alder reaction furan (IMDAF) reaction between starting 1-(furan-2-yl)but-3-en-1-amines and maleic anhydride, leading to 3a,6-epoxyisoindole-7-carboxylates, was studied as well.

Application of Amine-based Ru Compounds in the Olefin Metathesis of Methyl Eugenol: A Comparison with Grubbs Catalysts

Methyl eugenol olefin metathesis was conducted with non-carbene Ru-complexes ([RuCl2(PPh3)2amine]) in the absence and presence of SnCl2 or CuCl2 as additives and their catalytic activities were compared with that of a commercial Grubbs catalyst 2nd Generation (G2).