1471-03-0Relevant articles and documents
Understanding the competitive dehydroalkoxylation and dehydrogenation of ethers with Ti-C multiple bonds
Crestani, Marco G.,Olasz, Andras,Pinter, Balazs,Bailey, Brad C.,Fortier, Skye,Gao, Xinfeng,Chen, Chun-Hsing,Baik, Mu-Hyun,Mindiola, Daniel J.
, p. 2543 - 2550 (2013)
The divergent reactivity of a transient titanium neopentylidyne, (PNP)TiCtBu (A) (PNP = N[2-PiPr2-4- methylphenyl]2-), that exhibits competing dehydrogenation and dehydroalkoxylation reaction pathways in the presence of acyclic ethers (Et2O, nPr2O, nBu2O, tBuOMe, tBuOEt, iPr2O) is presented. Although dehydrogenation takes place also in long-chain linear ethers, dehydroalkoxylation is disfavoured and takes place preferentially or even exclusively in the case of branched ethers. In all cases, dehydrogenation occurs at the terminal position of the aliphatic chain. Kinetics analyses performed using the alkylidene-alkyl precursor, (PNP)TiCHtBu(CH 2tBu), show pseudo first-order decay rates on titanium (kavg = 6.2 ± 0.3 × 10-5 s-1, at 29.5 ± 0.1°C, overall), regardless of the substrate or reaction pathway that ensues. Also, no significant kinetic isotope effect (k H/kD ～ 1.1) was found between the activations of Et2O and Et2O-d10, in accord with dehydrogenation (C-H activation and abstraction) not being the slowest steps, but also consistent with formation of the transient alkylidyne A being rate-determining. An overall decay rate of (PNP)TiCHtBu(CH 2tBu) with a t1/2 = 3.2 ± 0.4 h, across all ethers, confirms formation of A being a common intermediate. Isolated alkylidene-alkoxides, (PNP)TiCHtBu(OR) (R = Me, Et, nPr, nBu, iPr, tBu) formed from dehydroalkoxylation reactions were also independently prepared by salt metatheses, and extensive NMR characterization of these products is provided. Finally, combining theory and experiment we discuss how each reaction pathway can be altered and how the binding event of ethers plays a critical role in the outcome of the reaction.
Technological method for preparation of allyl ether compounds
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Paragraph 0059-0061, (2017/02/17)
The invention discloses a technological method for preparation of allyl ether compounds; the technological method can obtain the high-purity allyl ether compounds in low cost and high yield, has the advantages of high selectivity of the allyl ether compounds, less side reaction, easy separation and purification of the products, friendly technological process environment and the like, and is suitable for large-scale industrialized production.
PROCESS FOR PRODUCING ETHER COMPOUNDS IN PRESENCE OF A COPPER (II) SALT
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Page 46-47, (2008/06/13)
A process for producing allylic ether compounds in presence of a catalyst comprising at least one Cu(II) salt by reaction of an allylic alcohol with either itself or another alcohol.
