Naming ethers

The addition of a diethyl ether solution of ZnCl2 to in situ prepared LiC6F5 (Scheme 11) yielded initially an oily product, which was identified as a mixture of Zn(C6F5)2 and its diethyl etherate, namely [Zn(C6F5)2(OEt2)2].38 After multiple vacuum distillations, ether-free Zn(G6F5)2 11 was obtained as a free-flowing powder. 

As these acetals could be converted into the 4,6-O-ethylidene derivatives on treatment with acid, it was reasoned that use of a cyclic vinyl ether, namely, 3,4-dihydro-2H-pyran, might prevent this second process, thus leading to a more useful method of selective acetalation.338 An equimolar reaction with methyl a-D-glu-copyranoside for 4 days in N,N-dimethylformamide led to utilization of 88% of the glycoside, and the 6-(tetrahydropyran-2-yl) ether constituted —85% of the crude reaction-product. In contrast to the steric control apparent in this instance, reaction of 3,4-dihydro-2H-pyran with the axial and equatorial hydroxyl groups in dl-1,4,5,6-tetra-O-acetyl-mi/o-inositol was completely unselective,339 a fact that has been rationalized310 in terms of the probable mechanism of these reactions. 

A vinyl ether, namely, methyl 5,6-dideoxy-2,3-0-isopropylidene-j8-D-erj/thro-hex-4-enofuranoside, has been treated with bromine in chloroform or carbon tetrachloride126 a brominated product was not isolated, but it was observed that there was instantaneous consumption of a large excess of bromine. Presumably, a facile loss of hydrogen bromide can lead to degradation products which also can consume bromine. 

The alternative to this 0,0-acetal formation is the sequence of addition and El reaction. As a matter of fact, this is familiar from the transformation of alcohols with carbonyl compounds, but only occurs in some (very rare) cases. This is illustrated by Figure 9.31 using acid-catalyzed transformations of ethanol with two /3-diketones as an example. Here, enol ethers, namely 3-ethoxy-2-cyclopentene-l-one and 3-ethoxy-2-cyclohexene-l-one, respectively, are... 

During their preparation of fluorinated ethers ArOCF2CHFRORf from the reactions of sodium phenoxides with perfluoroalkyl vinyl ethers, namely CF2=CFORf [Rf=C3F7, C3F7OCF(CF3)=CF2, and Me02CCF2CF20CF(CF3)=CF2], Feiring and Wonchoba117 found that brominated and chlorinated products were also formed when hexachloroethane and 1,2-dibromotetrafluoroethane, respectively, were present (equation 75). While they... 

A Common Names (Alkyl Alkyl Ether Names)... 

Simple ethers are usually assigned common names. To do so, name both alkyl groups bonded to the oxygen, arrange these names alphabetically, and add the word ether. For symmetrical ethers, name the alkyl group and add the prefix di-. 

Translation of these results into compound I leads to structure X. Unraveling of the strained zwitterion XI derived from this would yield keto aldehyde XII, a structure that plays a central role in the various possible reaction mechanisms that branch off from the starting material I. Furthermore, under photo-lytic conditions, some alkenes react with carbonyl compounds to form four-membered cyclic ethers, namely, oxetanes, by way of a [2-1-2] cycloaddition reaction known as the Patemo-Buchi process. Such a reaction would be all that is necessary to convert XII into the bicyclic cyclopropanone XIII required for the Favorskii-type rearrangement (see Scheme 42.3). Splitting by methanol attack would directly yield compound II. 

The yellow heartwood of this ])lant yielded nigakinone, C15H10O3N2 (mp 224°) (LXXXIXa) and its 0-methyl ether, namely 4,5-dimethoxy-canthin-6-one, C16H12O3N2 (mj) 14(i°) (LXXXIXb). Oxidation of the former with permanganate generated methyl /3-carboline-l-carboxylate (mp 168°) 161). 

A new C-allyl cardano 1 derivative formed by Claisen rearrangement of an allyl ether namely, 2-allyl-3n-pentadecyl-6-tert-butylphenol had comparable antioxidant properties to the well known compounds DBHA and BHT, respectively 2,6-di-tert-butyl-4-methoxyphenol and 2,6-di-tert-butylphenol [252], The 2-allyl compound is related in properties to the precursor 2-tert-butyl-5n-pentadecylphenol (see, e.g. p. 542 in ref.[l] and [253] and to the hindered phenols [254],... 

In many of its source plants it is associated with one or two of its 0-desmethyl ethers, namely, jatrorrhizine and columbamine, which form sparingly soluble iodides along with that of palmatine. The mixed iodides are digested with aqueous alkali in which the phenolic compounds dissolve leaving the sparingly soluble palmatine iodide which may be purified by recrystallization from much boiling water. 

In this experiment/ Williamson wrote, "the two theories cross one another, and must lead to different results," with the actual result demonstrating the ideas of Gerhardt and Laurent. He underlined the point even more strongly by preparing additional novel asymmetric ethers, namely ethyl-amyl ether and methyl-amyl ether. The argument was proven, he asserted—a beautiful example of an unanswerable ex-perimentum crucis. 

Assign the lUPAC name to each of the following ethers. Name the smaller alkyl group as the aUcoxy group. 

Combine the two names from Steps 1 and 2, giving the alko name first, to form the ether name ... 

Ether formation, (a) Give the equation for the conversion of methanol to the corresponding ether. Name the ether formed, (b) How many ethers are possible when a mixture of CH3OH and CHjCHjOH reacts with concentrated sulfuric acid (c) Would you choose the method in part (b) to synthesize methyl ethyl ether, CHjOCHaCHj Explain. 

Cellulosics comprise of a class of polymers which include cellulose nitrate, three organic esters, namely, cellulose acetate, cellulose acetate propionate, and cellulose acetate butyrate and one ether, namely, ethyl cellulose. Cellulose acetate film or cellophane finds application in the packaging. industry. Cellulose acetate butyrate is the material used between sheets of glass when making safety glass for the automotive industry. Xanthanated cellulose or rayon is used for making fabrics. 

Dibenzocrown ethers, namely dibenzo-18-crown-6 and -24-crown-8 by similar treatment with a larger excess of the reagent (20 equivalents) gave the corresponding disulfonyl chlorides. For example, dibenzo-18-crown-6 ether 500 afforded the disulfonyl chloride 501 as a mixture of stereoisomers, showing that chlorosulfonation of the dibenzocrown ethers does not occur regioselectively. The chlorosulfonyl and dichlorosulfonyl derivatives were converted into sulfonamides by reaction with ammonia and amines. 

Ether Name Boiling point (°C) 1-Alkanol Boiling point (°C)... 

Arrange these names alphabetically and add the word ether. For symmetrical ethers, name the alkyl group and add the prefix di. 

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