Ether , functional group

For the most part, cyclic ethers behave like acyclic ethers. The chemistry of the ether functional group is the same, whether it s in an open chain or in a ring. Common cyclic ethers such as tetrahydrofuran and dioxane, for example, are often used as solvents because of their inertness, yet they can be cleaved by strong acids. 

Epoxide (Section 7.8) A three-membered-ring ether functional group. 

Compound (11) contains enone and ether functional groups but only disconnection of the enone will lead to slmplifIcatlon. 

It has been often proposed that the units of coal structure are linked by ether linkages. Recently, Ruberto and his coworkers (7,8), Ignasiak and Gawlak (9) concluded that a significant portion of the oxygen in coal occurs in ether functional groups. 

The ion-transporting ability of monensin results principally from its many ether functional groups, and it is an example of a polyether antibiotic. 

The above observations with respect to the reactivities of monomers IV-VI can be explained by postulating a direct interaction of the carbonyl and the ether functional groups with the propagating cationic center. This can occur by either an inter- or intramolecular process. As shown in equation 5, intramolecular backside attack by the ester carbonyl group of the d,l-trans IV isomers at either carbon of the protonated or alkylated epoxy group gives rise to bicyclic dioxacarbenium ions IX and X. 

It should be noted that, in the case of [(R)(Me)SiCp2YR], the TOF of the hydrogenation of 1-hexene decreases dramatically, from 11 100 h 1 (R=Me) to 200 h 1 when an ether functional group is bound on the ansa bridge (R=(CH2)5OMe), which shows the sensitivity of Group III metal complexes towards polar functionalities [121]. 

The reaction tolerates ketone, chloride, internal C=C bonds, esters, nitriles, and ether functional groups. Given that the DIBAL-H reduction of acid derivatives often suffers from over-reduction to alcohols, these catalytic procedures are of synthetic value for laboratory-scale syntheses. However, it is likely that the requirement for excess (tBuCO)20 will prevent this reaction from ever being used in commercial production. 

The present report gives the methods used and the data obtained for acid, ester, aldehyde, ketone, amide, hydroxyl, and ether functional groups in kero-gen and trona acids. These methods may be applicable also in studying coals and other carbonaceous materials. 

Note that the ether functional group can be tolerated in making a Grignard reagent (part b). 

Amberlite XAD-2, functionalized by coupling to quinalizarin [1,2,5,8-tetrahydroxyanthraquinone] by an -N=N- spacer Lignin derivatized with methyl thio ether functional groups... 

Brevetoxin B is a fascinating naturally occurring compound that was synthesized in the laboratory in 1995. It is packed with ether functional groups in ring sizes from 6 to 8. 

This is an important example because an enol ether functional group is present in the product and this can be hydrolysed to a ketone in aqueous acid (see Chapter 21). 

Adjacent functional groups appear to weaken C-H bonds radicals next to carbonyl, nitrile, or ether functional groups, or centred on a carbonyl carbon atom, are more stable than even tertiary allcyl radicals. 

Glycol ethers possess both alcoholic and ether functional groups and are milder in odor. They display water miscibility, strong solvency, and slow evaporation. N-Butanol and denatured alcohol are the most commonly used oxygenated solvents. 

The defining arrangement for the ether functional group is oxygen between two carbons. (See figure 2.1.7.) One particular ether, diethyl ether, is known for its soporific effects on the mammalian brain, an effect that was widely appreciated by surgical patients when it was perfected as an anesthetic. 

The results indicate that the Sternberg alkylation reaction can be effectively used for the introduction of labeled reagents into coal and that the alkylation products can be separated and analyzed by NMR methods. The results of the NMR analyses establish that the different molecular weight fractions contain different amounts of C butylation and O butylation products. The distribution of ethereal functional groups also appears to depend upon the molecular weight. 

An alternative, and more widely used, method is to reduce alkynes with LiAlH4. This reaction works only if there is a hydroxy or an ether functional group near to the alkyne, because it relies on delivery of the reducing agent to the triple bond through complexation to this oxygen atom. 

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