Ethers, simple

The strength of this bonding depends on the kind of ether Simple ethers form relatively weak complexes with metal ions but Charles J Pedersen of Du Pont discovered that cer tain polyethers form much more stable complexes with metal ions than do simple ethers Pedersen prepared a series of macrocyclic polyethers cyclic compounds contain mg four or more oxygens m a ring of 12 or more atoms He called these compounds crown ethers, because their molecular models resemble crowns Systematic nomencla ture of crown ethers is somewhat cumbersome and so Pedersen devised a shorthand description whereby the word crown is preceded by the total number of atoms m the ring and is followed by the number of oxygen atoms... 

The strength of this bonding depends on the kind of ether. Simple ethers fonn relatively weak complexes with metal ions, but Charles J. Pedersen of Du Pont discovered that certain polyethers fonn much more stable complexes with metal ions than do simple ethers. 

A hydroxide nucleophile is needed to synthesize an alcohol, and salts such as NaOH and KOH are inexpensive and commercially available. An alkoxide salt is needed to make an ether. Simple alkoxides such as sodium methoxide (NaOCH3) can be purchased, but others are prepared from alcohols by a Brpnsted-Lowry acid-base reaction. For example, sodium ethoxide (NaOCH2CH3) is prepared by treating ethanol with NaH. 

The great majority of applications of the Birch reduction have been centered on aromatic ethers, simple alkylbenzenes and bicyclic and polycyclic aromatic hydrocarbons. Over the past decade or so, however, there has been increasing attention given to other derivatives. The reductions of aromatic acids and amides have been placed on a systematic basis, while new procedures have been established for substrates which have until recently been regarded as unsuitable candidates for reduction, e.g. aromatic ketones and esters, and even nitriles,... 

Cleavage of p-methoxybenzyl ethers. Simple exposure to CF3COOH effects the cleavage of the ether group at C-5 of furanose derivatives while retaining the primary ether at C-6. 

Although epoxides are technically classed as ethers, we discuss them separately Epoxide because of their exceptional chemical reactivity compared with other ethers. Simple A cyclic ether in which oxygen is epoxides are named as derivatives of oxirane, the parent epoxide. Where the epoxide three-membered ring,... 

Borowitz has encountered perhaps predictable difficulties in the attempted extension of his synthesis of macrocyclic ketolactones preparation of the requisite enol ethers, simple in the bicyclo[4,4,0) series, presented considerable difficulty in the bicyclo[5,5,0] series. A variant of such an oxidative enol ether cleavage has been reported, where oximinolactones are formed... 

Computation of the conformational energies of 2-methoxytetrahydropyran, a model for the methyl aldopyranosides, gave results in agreement with experimental observations. A preference for the axial conformer was apparent, but the nature of the stabilizing factor (anomeric effect) was not resolved. Force-field calculations have been extended to include alcohols, ethers, simple acetals, and 2-methoxytetrahydropyran. 2 The preference of 2-methoxytetrahydropyran for the axial conformer was attributed to interaction of the axial lone-pair orbital on the ring-oxygen atom with the axial C—O bond of the methoxy-group, which can be represented by the resonance structure (501) (see also, Vol. 6, p. 163). 

Colourless liquids. Alcohols hydrocarbons aldehydes ketones simple esters low moLwt. ethers simple halogeno-hydro-carbons low mol.wt. saturated aliphatic adds and their anhydrides formamide simple amines (when pure). 

Base hydrohalides (cold) acyl halides aliphatic -halogeno-ethers simple alkyl iodides (slowly) a few tertiary halides (slowly) some -halo-geno-esters (when warm) JV halogenated compounds (when cold). 

Alkylation of a stannyl enol ether is specifically initiated by an alkyl radical generated from an alkyl halide and a radical initiator such as 2,2 -azobisisobutyronitrile (AIBN) (Scheme 3-197). In addition, the three-component reaction of a stannyl enol ether, simple iodoalkane and an electron-deficient alkene proceeds successfully with anti-stereochemistry. 

Chem. Descrip. Nonyl phenol ethoxylate 6 moles EO Ionic Nature Nonionic Chem. Analysis 0.05% max. ash Uses Detergent, emulsifier for a wide range of oil and waxes Properties APHA 80 max. cl. to si. hazy liq. sol. in water, alcohol, glycol ethers, simple esters and most aromatic solvents insol in aliphatic solvents and mineral oils. sp. gr. 1.025-1.045 cloud pt. (1% aq.) 61-65 C HLB 11 Canocol NP-9 [Centro China]... 

Properties APHA 80 max. cl. to si. hazy liq. sol. in water, alcohol, glycol ethers, simple esters and most aromatic solvents insol in aliphatic solvents and mineral... 

Properties Pt-Co 150 max. cl. Iiq. disp. in water, sol. in simple alcohols, glycol ethers, simple esters, aromatics, olein and unsat. hydrocarbons limited sol. in common aliphatic hydrocarbon soivs. sp.gr. 1.046 vise. 340 cP (20 C) hyd. no. 110-117 0.3% w/w water Teric B1 [ManroSA ]... 

In contrast to the vinyl ethers, simple alkenes such as isobutylene and allyltrimethylsilane trap oxyallyl 37 in a concerted ene-reaction to ketoalkenes 45 and 46 in yields of 15 to 25% (Scheme 6). The E- and Z- silylketones 46 are formed in about equal amounts. Noyori has reported a similar ene-reaction for oxyallyl-iron complexes with isobutylene. ... 

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