Transetherification reaction

The first silicone surfactants were prepared by reaction of alkoxy-functional silicones with hydroxyl terminated polyethers using the transetherification reaction [7] ... 

Synthesis of Vinyl Ethers of (R)-(-)-2,2-Diphenylcyclopen-tanol. The preparation of DCP-derived vinyl ethers usually involves mercuric acetate-catalyzed transetherification reaction with DCP and a corresponding vinyl ether (eq 1 ). ... 

The desulfurization of alkylsulfanylpteridines, usually a facile reaction in A-heterocyclic chemistry, is similarly problematic. The use of an aluminum-copper alloy in ethanolic alkali with 4-pentyloxy-6-propionyl-7-propylsulfanylpteridin-2-amine (3, X = PrS) gives a mixture of 4-pentyloxy- (4, Y = OC5Hn) and 4-ethoxy-6-propionylpteridin-2-amine (4, Y = OEt). The ethoxy product arises from a transetherification reaction.182... 

CROP is only reported for a limited number of cyclic ethers that exhibit enough ring strain to be readily opened. In addition, the rather similar nucleophilicity of the ether moieties in the monomers and the ring-opened polymers together with the reactive cationic oxonium species, often leads to the occurrence of transetherification reactions, complicating the development of living CROP methods. This section will focus on the living CROP of ethylene oxide, oxetane, and tetrahydrofuran. 

A completely distinct synthesis of the thiophene heterocycle has been published starting with 2,3-dimethoxybutadiene and SCI2 [28], In the last step of this EDOT synthesis, a transetherification reaction as mentioned above is necessary, using ethylene glycol. 

The package stability of alcohol-soluble resole resins and their compatibility with epoxy resins can be improved by partial conversion of the methylol groups to ethers. Allyl ethers have been used with epoxy resins in interior can coatings. Low molecular weight butyl ethers are used with acid catalysts to cross-link epoxy resins and other hydroxy-substituted resins, by etherification and transetherification reactions (148). 

An intramolecular phosphoric acid-catalyzed asymmetric 5 2-type alkylation reaction of alcohols with racemic secondary benzylic ethers resulted in a catalytic asymmetric transetherification reaction to form benzo[c]furan species via the potential of asymmetric Bronsted acid catalysis for the activation of normally unreactive functional groups such as ethers and potentially other less reactive substrates (13AGE3490). 

According to the authors, the cationic species present in the polymerization mixture participate in not only transacetaliza-tion but also transetherification reactions, yielding copolymers with the polyacetal and poly(ethylene oxide) blocks (see Scheme 1). These copolymers can function as the in sitM-formed suspension stabilizers adsorbed onto the surface of polyacetal particles via the polyacetal blocks and with the poly( ethylene oxide) segments providing steric stabilization. 

Palladium complexes have also been used to generate vinyl ethers through transetherification reactions [103], In addition to simple substrates, this chemistry has been extended to steroidal substrates (Scheme 2.75) [104]. The catalyst was a phenanthroline complex of palladium acetate, and ethyl vinyl ether served as the source of the vinyl fragment. The reaction conditions were mild, but the dmation of the reaction was long (4 d). 

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