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Parents similarity

A few experimenters have found IR bands which they assign to adsorbed CO bridging two chromium atoms (2-4). If correct this would indicate that at least some of the chromium atoms have close neighbors. These assignments are very uncertain, though, and even if correct do not necessarily imply a paired active site, or even a dichromate parent. Similar claims are also made for chromocene/silica, in which pairing seems most unlikely. [Pg.55]

Meta-model conflicts Meta-model conflicts occur when the resulting Merge violates the constraints of a specific model, but not the constraints mandatory for all models. This is just like how in Rondo [Melnik et al. 2003] an SQL column can belong to only one table there is nothing inherent in having structured data that says that a child must belong to only one parent. Similarly to Rondo, these conflicts must be resolved elsewhere. [Pg.239]

Protonation of formic acid similarly leads, after the formation at low temperature of the parent carboxonium ion, to the formyl cation. The persistent formyl cation was observed by high-pressure NMR only recently (Horvath and Gladysz). An equilibrium with diprotonated carbon monoxide causing rapid exchange can be involved, which also explains the observed high reactivity of carbon monoxide in supera-cidic media. Not only aromatic but also saturated hydrocarbons (such as isoalkanes and adamantanes) can be readily formylated. [Pg.196]

Similar to oxonium ions, our studies of sulfonium ions also showed protosolvolytic activation in superacids to give sulfur superelectrophiles. The parent sulfonium ion (HjS ), for example, gives H4S (diprotonated hydrogen sulfide) in superacids. [Pg.197]

Diols are almost always given substitutive lUPAC names As the name of the prod uct m the example indicates the substitutive nomenclature of diols is similar to that of alcohols The suffix dwl replaces ol and two locants one for each hydroxyl group are required Note that the final e of the parent alkane name is retained when the suffix begins with a consonant ( diol) but dropped when the suffix begins with a vowel ( ol)... [Pg.634]

Focants of substituents of symmetrically substituted derivatives of symmetrical amines are distinguished by primes or else the names of the complete substituted radicals are enclosed in parentheses. Unsymmetrically substituted derivatives are named similarly or as A-substituted products of a primary amine (after choosing the most senior of the radicals to be the parent amine). For example. [Pg.27]

Tensile Strength and Elongation. The tensile strength of latex mbber foam has been shown to depend on the density of the foam (149,177) and on the tensile strength of the parent mbber (177,178). At low densities the tensile modulus approximates a linear relation with density but kicreases with a higher power of density at higher densities. Similar relations hold for polyurethane and other flexible foams (156,179,180). [Pg.413]

Ketones oxidize about as readily as the parent hydrocarbons or even a bit faster (32). Although the reactivities of hydrogens on carbons adjacent to carbonyl groups are perhaps doubled, the effect is small because one methylene group is missing in comparison to the parent hydrocarbon. Ketones oxidize less readily than similar primary or secondary alcohols (35). [Pg.336]

Aldehydes are important products at all pressures, but at low pressures, acids are not. Carbon monoxide is an important low pressure product and declines with increasing pressure as acids increase. This is evidence for competition between reaction sequence 18—20 and reaction 21. Increasing pressure favors retention of the parent carbon skeleton, in concordance with the reversibiUty of reaction 2. Propylene becomes an insignificant product as the pressure is increased and the temperature is lowered. Both acetone and isopropyl alcohol initially increase as pressure is raised, but acetone passes through a maximum. This increase in the alcohoLcarbonyl ratio is similar to the response of the methanoLformaldehyde ratio when pressure is increased in methane oxidation. [Pg.341]

Isobutane shows the usual NTC and cool flame phenomena (78,154,157,158). As the pressure is iacreased, the expected iacrease ia oxygenated products retaining the parent carbon skeleton is observed (96). Under similar conditions, isobutane oxidizes more slowly than / -butane (159). There are stUl important unresolved questions concerning isobutane VPO (160). [Pg.342]

Dimeric aldoketenes and ketoketenes of P-lactone stmcture show a chemical behavior which is not much different to that of diketene. Thus nucleophiles add ia similar fashion to give derivatives of 3-ketoacids which are mono- or dialkylated at C-2 (aldo- and ketoketene dimers, respectively), but the reaction can often be slower than with the parent compound and, ia case of long-chain or bulky substituents, may not proceed at all. Other reactions can proceed differendy than those with diketene. For an overview of important reactions of aldoketene and ketoketene dimers see Reference 122. [Pg.479]

Ammonia forms a great variety of addition or coordination compounds (qv), also called ammoniates, ia analogy with hydrates. Thus CaCl2 bNH and CuSO TNH are comparable to CaCl2 6H20 and CuSO 4H20, respectively, and, when regarded as coordination compounds, are called ammines and written as complexes, eg, [Cu(NH2)4]S04. The solubiHty ia water of such compounds is often quite different from the solubiHty of the parent salts. For example, silver chloride, AgQ., is almost iasoluble ia water, whereas [Ag(NH2)2]Cl is readily soluble. Thus silver chloride dissolves ia aqueous ammonia. Similar reactions take place with other water iasoluble silver and copper salts. Many ammines can be obtained ia a crystalline form, particularly those of cobalt, chromium, and platinum. [Pg.338]

Although the antibacterial spectmm is similar for many of the sulfas, chemical modifications of the parent molecule have produced compounds with a variety of absorption, metaboHsm, tissue distribution, and excretion characteristics. Administration is typically oral or by injection. When absorbed, they tend to distribute widely in the body, be metabolized by the Hver, and excreted in the urine. Toxic reactions or untoward side effects have been characterized as blood dyscrasias crystal deposition in the kidneys, especially with insufficient urinary output and allergic sensitization. Selection of organisms resistant to the sulfonamides has been observed, but has not been correlated with cross-resistance to other antibiotic families (see Antibacterial AGENTS, synthetic-sulfonamides). [Pg.403]

Monophosphams. The similar tetrahedral geometry and bond lengths of tetracoordinate phosphoms(V) compared to those of sulfur(VI) suggested that phosphonic and phosphinic acid groups might act as biososteres for the sulfonic acid moiety in the parent monobactams. The... [Pg.63]

The tri-, tetra-, penta-, and hexahydrates of boron phosphate have been reported. AH of these decompose rapidly in water to give solutions of the parent acids. Anhydrous boron phosphate hydroly2es in a similar fashion, though the reaction proceeds quite slowly for material that has been ignited at high temperatures. [Pg.209]

A.n log ue Synthesis. Two notable examples, in which analogues have greater therapeutic indexes than the parent dmgs, have been identified in Phase I trials. These are carboplatin (29) and ado2elesin (37) (35). Carboplatin s approval was based on its comparable efficacy to cis-platinum (28) and its more favorable toxicity profile, ie, reduced and delayed episodes of emesis, reduced ototoxicity, etc. On the other hand, ado2elesin, a totally synthetic analogue of natural product CC1065, has demonstrated a similar potency and antitumor activity profile as its natural prototype but is devoid of the delayed death UabiUty associated with the parent dmg in animals (36). [Pg.444]

Hydroxyphthalazin-l(2//)-one is obtained in a smooth reaction between phthalic anhydride and hydrazine hydrate and this is again the starting compound for many 1-substituted and/or 1,4-disubstituted phthalazines. The transformations of 1,4-dichloro-phthalazine, which is prepared in the usual manner, follow a similar pattern as shown for pyridazines in Scheme 110. On the other hand, phthalonitrile is the preferential starting compound for amino- and hydrazino-phthalazines. The most satisfactory synthesis of phthalazine is the reaction between a,a,a, a -tetrachloro-o-xylene and hydrazine sulfate in sulfuric acid (67FRP1438827), alt iough catalytic dehalogenation of 1-chloro- or 1,4-dichloro-phthalazine or oxidation of 1-hydrazinophthalazine also provides the parent compound in moderate yield. [Pg.56]


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See also in sourсe #XX -- [ Pg.19 ]




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Parenting

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