Some further examples

Some further examples of Lewis acids follow ... 

Use of hyphens single- and multiple-word names. The general rule is to determine whether the parent is itself an element or compound. If so, then the name is written as a single word if not, then the name is written as multiple words. Methylbenzene is written as one word, for instance, because the parent—benzene—is itself a compound. Diethyl ether, however, is written as two words because the parent—ether—is a class name rather than a compound name. Some further examples follow ... 

The synthesis of enantiomerically enriched vinyl carbamates is described in Section 1.3.3.3.8.2.2. by applying this procedure, these were also obtained efficiently in the racemic form. Some further examples of substituted carbamates are collected below ... 

The multifunctional initiators may be di- and tri-, azo- or peroxy-compounds of defined structure (c.g. 20256) or they may be polymeric azo- or peroxy-compounds where the radical generating functions may be present as side chains 57 or as part of the polymer backbone."58"261 Thus, amphiphilic block copolymers were synthesized using the polymeric initiator 21 formed from the reaction between an a,to-diol and AIBN (Scheme 7.22).26 Some further examples of multifunctional initiators were mentioned in Section 3.3.3.2. It is also possible to produce less well-defined multifunctional initiators containing peroxide functionality from a polymer substrate by autoxidalion or by ozonolysis.-0... 

In the situation where most atoms leave the reservoir soon and few of them remain very long (Fig. 4-4c), x is larger than tq (the "short circuit" case). Some further examples of age distributions and relations between x and tq are given in Lerman (1979). 

Recognition of the basic nature of condensation polymers did not advance perceptibly from the early work of Lourengo and Kraut up to 1910 or 1920, or even somewhat later. In fact, evidence of retrogression could be cited. Some further examples serve to illustrate the state of affairs prevailing at the turn of the century. 

Infrared measurement of additive concentrations is a more complex analysis than initially expected, as some additives may undergo a variety of chemical reactions during processing, as shown by Reeder et al. [128] for the FTIR analysis of phosphites in polyolefins. Some further examples of IR work refer to PVC/metal stearates [129], and PE/Santonox R [68,130]. Klingbeil [131] has examined the decomposition of various organic peroxyesters (TBPB, TBPP, TBPA and TBPO) and a peroxidicarbonate (BOPD) as a function of pressure, temperature and solvent by means of quantitative FTIR using an optical high p, T reaction cell. 

We have already discussed carbanion addition to RC02Et (Claisen ester condensation, p. 229), and also their reduction by Li AlH4e (p. 214) some further examples of nucleophilic attack will now be considered. 

No more theory is required to start investigating CA applications, so we turn now to some further examples. 

We shall illustrate and extend the ideas in the last section by looking at some further examples, one in our invented WHILE programming language, and others in "real" programming languages. 

Other heterocyclic systems prepared by a thionyl chloride reaction include fused thiazoles,71 thiatriazoles,72 oxathiins,73 and dithiins 74 some further examples are given in reviews.53... 

One might conclude this first section by commenting that the combination of room-temperature and cryogenic techniques now available promises to unravel some photochemical problems of considerable complexity. Before turning to some further examples, it is worth noting some very interesting recent experiments involving the gas phase photochemistry of Cr(CO) . 

Earlier sections of this review have already discussed results for quadrupolar nuclei in certain connections for Knight shifts (Sects. 3.4.3 and 3.4.4), for electric-field (Stark) effects upon NQCCs (Sect. 3.1), for measurements of NQCCs in GaN by static NMR and the effects of strain upon NQCCs (Sect. 3.2.1), for obtaining exchange couplings by MAS-NMR (Sect. 3.2.2), and for characterizing polytypes and defects in cubic polytypes by chemical shifts and NQCCs obtained from MAS-NMR (Sect. 3.3.2). This section will give some further examples of information about semiconductors obtained from the NMR of quadrupolar nuclei (see also [18]). 

Some further examples of infrared spectra are given in the section on the combined use of spectral data. 

Some further examples of the allyltrimethylsilane cross-metathesis reactions, originally investigated by Crowe, with more complex substrates were also in-... 

Some further examples of selective deprotection in the presence of other reducible functional groups are shown in Figs. 37-40. 

Some further examples of the reduction of adamantanones have highlighted that increasing the positive dipole on the C=0 using Lewis acids, or placing charged substituents at C(5) within the adamantyl framework, enhances face selectivities in borohydride and aluminium hydride reductions due to Cieplak effects. 

Many other applications of multi-photon absorption spectroscopy have meanwhile been reported in photochemistry and also in solid state physics, for instance, a new assignment of the band gap in alkali bromides by Froehlich et al Some further examples will be discussed in Section 111.10). 

This distinction between electron-cloud radii and structural radii is then used to refine the system of ionic radii due to Pauling and Goldschmidt. Some further examples of anion-anion contact are discussed, and a value deduced for the crystal radius of the hydride anion. These cases of anion-anion contact argue for the Pauling tradition and against the new electron-density-minimum (EDM) radii. 

For some further examples of this type see M. Asoaka. K. Shima, H. Takei, Tetrahedron Lett. 28, 5669 (1987) J. Chem. Soc., Chem. Commun. 1988. 430. 

Some further examples of stereoselective deprotonation/alkylation reactions of tricarbonyl-chromium complexed (V-methyl tetrahydroisoquinolines have been reported27. Starting with the enantiomerically pure (35)-methyl tetrahydroisoquinoline reaction with hexacarbonyl-chromium led to a mixture of endo- (40%) and exo- (60%) complexes, which were deprotonated with butyllithium and subsequently methylated with iodomethane. In this way methylation occurred firstly at the 4- and secondly at the 1-position. In all cases, the methyl group entered anti to the chromium complexed face. After separation of the alkylated complexes by chromatography and oxidative decomplexation, the enantiomerically pure diastereomers (—)-(l 5,35,47 )-and ( + )-(17 ,35,45)-1,2,3,4-tetrahydro-l,2,3,4-tetramethylisoquinolme were obtained, benzylic amines such as tetrahydroisoquinoline to 2-amino-4,5-dihydrooxazoles. Deprotona... 

Figure 7.2 Some further examples of the product of oxidation (after Nicolaou et...

One of the most characteristic reactions of the aminochromes is the ready formation of mono-derivatives with typical ketone reagents, e.g. semicarbazide, phenylhydrazine, etc. A relatively large number of derivatives of this nature have been prepared because of then-reported hemostatic activity (cf. refs. 2 and 3). Compounds of this type that had been described in the literature prior to December 1959 are listed in a previous review (Heacock3). Some further examples of this class of compounds have been described recently. They are N-ethylnoradrenochrome semicarbazone (84) (orange-red needles, m.p.180 215°)65 7-iodoadrenochrome methyl ether semicarbazone... 

There have been some further examples of the use of the Conrad-Limpach reaction on substituted 5-aminoquinolines for the synthesis of 4-hydroxy-1,7-phenanthrolines, although the products (see Section IV,F,1) should properly be designated as phenanthrolinones.169 Hot diphenyl ether is often employed as the medium for ring closure.170 Ethyl trifluoro-acetoacetate has been used successfully in place of ethyl aceto-acetate, and this variation has allowed entry to 2-trifluoromethyl-substituted 1,7-phenanthrolines.96 Extensions of the Conrad-Limpach type of synthesis starting with m-phenylenediamine (20) and utilizing diethyl ethoxymethylene malonate or ethyl ethoxalylacetate, reagents frequently used in quinoline syntheses, have afforded, after hydrolysis,... 

Some further examples have been reported of the catalytic reduction of quaternary salts of 4,7-phenanthrolines to the corresponding tetra-hydro analogs.229 238 Reduction of 4-methyl-4,7-phenanthrolinium iodide... 

An indication of the scope of the Knoevenagel synthesis of coumarins is apparent from Table 7, but some further examples utilizing the conventional procedure are worthy of mention partly because some of the products are naturally occurring compounds. Graveolone (375), a benzodipyran, is obtained from the chroman-4-one shown by cyclization of the acrylic acid (Scheme 117) (78IJC(B)570). 

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