Ketones 502 INDEX

The choice of which reactions to include is not an easy one. First there are the well known "Name Reactions", that have appeared in various monographs or in the old Merck index. Some of these are so obvious mechanistically to the modern organic chemistry practitioner that we have in fact omitted them for instance esterification of alcohols with acid chlorides - the Schotten-Baumann procedure. Others are so important and so well entrenched by name, like the Baeyer-Villiger ketone oxidation, that it is impossible to ignore them. In general we have kept older name reactions that are not obvious at first glance. 

Most important for the synthetic chemist is an index to the synthesis of functional groups, e.g. synthesis of alkenes from ketones, as well as conversion of ketones to alkenes. 

This section concludes with a reminder that, in addition to the hypohalous acids HOX and metal hypohalites M(OX) , various covalent (molecular) hypohalites are known. Hypochlorites are summarized in Table 17.22. All are volatile liquids or gases at room temperature and are discussed elsewhere (see Index). Organic hypohalites are unstable and rapidly expel HX or RX to form the corresponding aldehyde or ketone ... 

The ketone derivatives of the pseudo-ionone are converted under similar conditions into ketone-derivatives of the ionone. The pure ionone corresponds to the formula CjjHjjO, it boils under a pressure of 12 mm. at a temperature of about 128° 0., its specific weight is 0-935, and its index of refraction mD = 1-507. 

The preduct of condensation remaining in the distilling apparatus is purified by the fractional distillation in vacuo. Under a pressure of 12 mm. a liquid distils off at a temperature of from 143° to 145° C. This preduct of condensation of citral with acetone, which I term Pseudo-ionone, is a ketone readily decomposable by the action of alkalis. Its formula is CigHjoG, its index of refraction nT> = 1-527, and its specific weight 0-904. 

Another publication is the Index of Reviews in Organic Chemistry , complied by Lewis, Chemical Society, London, a classified listing of review articles. The first volume, published in 1971, lists reviews from 1960 (in some cases much earlier) to 1970 in alphabetical order of topic. Thus four reviews are listed under Knoevenagel condensation , five under Inclusion compounds , and one under Vinyl ketones. There is no index. A second volume (1977) covers the literature to 1976. Annual or biannual supplements appeared from 1979 until the publication was terminated in 1985. Classified lists of review articles on organometallic chemistry are found in articles by Smith and Walton and by Bruce.A similar list for heterocyclic chemistry is found in articles by Katritzky and others.See also the discussion of the Index of Scientific Reviews, page 1638. 

Examples of the protection of alkynes, carboxylic acids, alcohols, phenols, aldehydes, amides, amines, esters, ketones, and alkenes are also indexed on p. xvii. Section (designated with an A 15A, 30A, etc.) with protecting group reactions are located at the end of pertinent chapters. 

Detectability may be a significant problem with homologous series of unsaturated compounds, particularly //-alkanes. For these compounds, refractive index detection or evaporative light-scattering, both of which are described elsewhere in the book, may be of use. Indirect photometry is a useful detection scheme for compounds that do not absorb in the UV. Acetone, methylethyl ketone, methyl propyl ketone, methyl isopropyl ketone, methyl isobutyl ketone, and acetophenone are added to an acetonitrile/water mobile phase, generating a negative vacancy peak when the nonchro-mophoric analyte emerges and a positive peak if the ketone is adsorbed and displaced.70 Dodecyl, tetradecyl, cetyl, and stearyl alcohols also have been derivatized with 2-(4-carboxyphenyl)-5,6-dimethylbenzimidazole and the derivatives separated on Zorbax ODS in a mobile phase of methanol and 2-propanol.71... 

Smith, R. M. and Finn, N., Comparison of retention index scales based on alkyl aryl ketones, alkan-2-ones and 1-nitroalkanes for polar drugs on re-versed-phase high-performance liquid chromatography,. Chromatogr., 537, 51,1991. 

The SEC mechanism demands only an isocratic (constant composition) solvent system with normally a single solvent. The most frequently used organic solvents are THF, chloroform, toluene, esters, ketones, DMF, etc. The key solvent parameters of interest in SEC are (i) solubility parameter (ii) refractive index (iii) UV/IR absorbance (iv) viscosity and (v) boiling point. Sample solutions are typically prepared at concentrations in the region of 0.5-5 mg mL-1. In general an injection volume of 25-100p,L per 300 x 7.5 mm column should be employed. For SEC operation with polyolefins chlorinated solvents (for detector sensitivity and increased boiling point) and elevated temperatures (110 to 150 °C) are required to dissolve olefin polymer. HFIP is the preferred solvent for SEC analysis of polyesters and polyamides. 

Oxidative damage to membrane polyunsaturated fatty acids leads to the formation of numerous lipid peroxidation products, some of which can be measured as index of oxidative stress, including hydrocarbons, aldehydes, alcohols, ketones, and short carboxylic acids. 

On standing, the ketone gradually turns yellow, and the refractive index increases. Redistillation of such material gives pure ketone. 

These three chemical classes listed in the Colour Index are no longer of any practical significance. They are mentioned here only for their resemblance to quinonoid and ketone dyes already discussed. The chromogens are quinonimine (1.36), with amino or hydroxy auxochromes respectively in the indamines and indophenols, and a lactone ring (1.37) with a hydroxy auxochrome. 

Under the designation P.B.15 4, the Colour Index lists (3-Copper Phthalocyanine Blue types which are stabilized towards flocculation. These products show largely the same coloristic and fastness properties as P.B.15 3 types, but often exhibit much better rheology. As with stabilized a-Copper Phthalocyanine Blue types, stabilization through surface treatment has proven to decrease the solvent fastness of 3-Copper Phthalocyanine Blue, sometimes considerably so, making the pigment more sensitive to aromatics, alcohols, ethylene glycol, and ketones. 

Fig. 56. Dependence of specific refractive index increment on conversion of monomers to polymer for a styrene/acrylonitrile/methyl methacrylate terpolymer in methyl ethyl ketone at 20 °C and 436 nm. (a) - partial azeotrope, (b) terpolymer with composition distribution163 ...

Draw the structures of the bicyclo[3.1.0]hex-2-ene-2-carboxaldehyde, cis-jasmone, the Wieland-Miescher ketone and the bis-nor-analogue -which you may find through the "Subject index"- and ... 

G.l.c. papers of interest include the classification of 22 acyclic monoterpenoid alcohols according to retention indexes, resolution of cyclic ketones [e.g. ( )-menthone, ( )-isomenthone] as diethyl (+)-tartrate acetals, and the use of lanthanide shift reagents to resolve non-terpenoid racemic epoxides.The occurrence and prevention of monoterpenoid hydrocarbon isomerization during silica gel chromatography has been examined and the separation of monoterpenoids and sesquiterpenoids by gel permeation chromatography is reported. Monoterpenoid hydrocarbons have been selectively extracted from essential oils using dimethylsilicone. ... 

Furby (12) has developed a method for evaluating stocks in the lubricating oil range that results in a breakdown of components into asphaltenes, resins, wax, and dewaxed oil and provides a yield-viscosity index relationship for the dewaxed oil. The author has found such analyses very useful and inexpensive for evaluating a large number of potential lubricating oil stocks. Furby s method utilizes petroleum ether to precipitate asphaltenes, a fuller s earth-petroleum ether fractionation to isolate resins, methyl ethyl ketone-benzene dewaxing on the deasphalted-deresinified material to separate wax, and an adsorption fractionation to provide cuts from which the yield-viscosity index relationship for dewaxed, solvent-refined oil is obtained. 

Aldehyde, ketone, etc. are not indexed as these compounds appear on almost every page. 

These constants, which are related to the structure of the molecules, allow an evaluation of the forces of interaction between the stationary phase and the solute for different classes of compounds. An index with an elevated value indicates that the stationary phase has a strong affinity for compounds that contain particular organic functions. This leads to a greater selectivity for this type of compound. For example, in order to separate an aromatic hydrocarbon contained in a mixture of ketones, a stationary phase for which benzenes have a very different constant than butanone will be selected. These differences in indices appear in most manufacturers catalogues of chromatographic components (Table 2.1). McReynolds constants have more or less replaced Rohrschneider constants, which are based on the same principle but use different reference compounds. 

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