General Classes of Compounds

MetalIa-/3-diketonate complexes, such as 1, are conveniently prepared by reacting acylmetal carbonyl complexes with strong bases that can also react as nucleophiles, such as organolithium, Grignard, or boron hydride reagents [Eq. (1)]. These reactions can be followed by IR spectroscopy. 

Our recognition of these m-diacylmetalate complexes as metalla-/3-diketonate species led to an extension of this chemistry 1). Nucleophilic addition to carbonyl ligands of acyl complexes gave metalla-jS-diketonates of the following types [cis-(OC)4Mn(RCO)(R CO)], in which R is alkyl or benzyl and R is alkyl, alkoxide, or NMe2 [/ac-(OC)3(RNC)Mn(MeCO)2], where R is Me, C6Hu, or /-butyl [ds-(OC)4Re(RCO)(R CO)], in which R is alkyl or benzyl and R is alkyl or H and [(i7-C5H5)(OC)Fe(RCO)(R CO)], where R is alkyl and R is alkyl or benzyl. 

Casey et al. have studied the decarbonylation reactions of [cis-(OC)4M(MeCO)(PhCO)], in which M is Mn or Re (16,17). These complexes lose a carbonyl ligand to form five-coordinate intermediates of the type [(OC)3M(MeCO)(PhCO)]. Reversible methyl migration proceeds much more rapidly than does phenyl migration. In the course of these studies, a phosphine substituted rhena-/3-diketonate complex, [fac-(OC)3(Et3P)Re(MeCO) (PhCO)], was prepared. 

Neutral b/.v(acyl)Fe(CO)4 complexes have been reported by Stewart et al. (23). The acyl ligands have perfluoroalkyl substituents. These complexes are isoelectronic to the anionic diacyltetracarbonylmanganate species mentioned above. 

Metalla-/3-diketones are readily prepared by protonation of metalla-/3-diketonate anions. The first reported metalla-j8-diketone was the rhenaacetylacetone molecule [ds-(OC)4Re(MeCO)2]H (10) (1,24). Diagnostic indications of the formation of this type of complex are (1) the appearance of a cw-L2M(CO)4 pattern in the carbonyl C—O stretching 

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Two of the material systems shown in figure G2.16.3 are of particular importance. These are the ternary compounds fonned from group III elements such as A1 and Ga in combination with As and quaternary compounds fonned from Ga and In in combination with As and P [8,15,]. Ternary Al Ga s grown on GaAs is the best known of the general class of compounds Quaternary Ga In As grown on InP is... 

Higher order aUphatic quaternary compounds, where one of the alkyl groups contains - 10 carbon atoms, exhibit surface-active properties (167). These compounds compose a subclass of a more general class of compounds known as cationic surfactants (qv). These have physical properties such as substantivity and aggregation ia polar media (168) that give rise to many practical appHcations. In some cases the ammonium compounds are referred to as iaverse soaps because the charge on the organic portion of the molecule is cationic rather than anionic. 

The Subject Index of over 20 000 entries has been compiled from keywords, names and formulae in the text and tables. It covers general classes of compound, specific compounds, general types of reaction, specific and named reactions, spectral and other properties, and other topics in heterocyclic chemistry. More details are again given at the beginning of the index in Volume 8. 

This Formula Index consists of over 28 000 compounds that occur in the 6562 text pages of Volumes 1-6. Indexed compounds may appear in the text, equations, Schemes, Figures or Tables. Only specific compounds and not general classes of compound have been indexed the counter ion has been excluded. Limitations of space do not permit every coordination compound to be indexed each time it is mentioned, therefore compounds are only indexed when considered to be important in the context of the topic under discussion. 

LCEC has become a widely used analytical technique for biomedical analysis. Several reports appear each month deairibing new LCEC analyses or reporting results obtain-with LCEC. While space does not permit a complete review of all bitwhemical applications, this section will consider applications of LCEC to general classes of compounds to provide an overview of the uses of this technique. For a thorough survey of the literature, a bibliography of LCEC applications is available... 

The synthesis of 177-2,1-benzothiazine 2,2-dioxide was pioneered by Loer and coworkers <66JOC3531> and also by the Rossi group <66AC(R)728 66AC(R)741>. The general class of compounds is represented in Figure 4. 

Monoclonal antibodies (mAbs) these comprise a general class of compounds with defined structure and typically with molecular weight around ISOkDa. 

Only the general class of compounds formed is indicated. For details of specific compounds consult the references. b Only 138d, e. c Mainly 139a, b. d Mainly 140a, b. 

Higher order aliphatic quaternary compounds, where one of the alkyl groups contains 10 carbon atoms, exhibit surface-active properties. These compounds compose a subclass of a more general class of compounds known as cationic surfactants. 

In Table 1.7 are listed the general classes of compounds in descending order of preference for citation as suffixes, that is, as the parent or characteristic compound. When oxygen is... 

Many chemical methods have been tested and proposed for detecting adulteration. Some methods are non-specific and measure a general class of compounds whereas others are specific for a given compound. Each type has advantages and disadvantages in terms of analytical time, economy, difficulty and ease of circumvention. The various classes of citrus constituents will be discussed separately. 

To what general classes of compounds do the following belong What are some of their properties... 

List five general classes of compound that are collectively known as lipids. Describe the essential differences between (a) plasmalogens and sphingomyelins and (b) cerebrosides, sulphatides and gangliosides. 

Lepidopterous sex pheromones, particularly those produced by female moths, have been primarily determined to be unsaturated normal aliphatic alcohols, esters, or aldehydes (3, 1 , 71). In the present review, emphasis will be placed on the sex pheromones that either are structurally distinctive or representative of the general classes of compounds that are identified with lepidopterous species. Notwithstanding the terminological inexactitude that characterizes the research on lepidopterous exocrine products (72), these compounds will be referred to as sex attractants or pheromones unless otherwise indicated. 

Raman spectroscopy has played a significant role in the characterization of electrical conductors, some of which have become superconductors. There are three general classes of compounds that have been investigated using Raman spectroscopy. These are the high- Tc superconducting ceramics the low-7 ... 

Hydroxyl Substitution Products.— All of the preceding facts lead to the conclusion that alcohol is a compound in which the ethyl radical is linked to the hydroxyl radicalj i.e, it is the hydroxyl substiltUion product of ethane or hydroxy ethane. Alcohols thus belong to the same general class of compounds as the halogen substitution products. The relationship between the hydrocarbons, the halogen substitution products, alkyl halides and the hydroxyl substitution products, alcohols, may be shown as follows ... 

To what general class of compounds does potassium persulfate belong ... 

Problem 26.7 (a) Predict the product of the acetoacetic ester synthesis in which ethyl bromoacetate (why not bromoacetic acUH) is used as the halide. To what general class of compounds does this product belong (b) Predict the product of the acelo-acelic ester synthesis in which benzoyl chloride is used as the halide in which chloro-acetone is used as the halide. To what general classes of compounds do these products belong ... 

As a general class of compounds, PAHs have low acute toxicity. 

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