Reaction, displacement

Reaction displacements. If the restraints are not considered rigid and there is a predictable movement of the restraint under load, this may be treated as a compensating displacement. 

Total Displacement Strains Thermal displacements, reaction displacements, and externally imposed displacements aU have equivalent effects on the piping system and must be considered together in determining total displacement strains in a piping system. 

Halogenation of the acetyl compound 14 affords the corresponding chloroketone (15). (Compound 14 is obtainable by acylation of the quinolol. The pyridine ring is, of course, deactivated in the acidic conditions of the reaction.) Displacement of halogen by means of isopropylamine leads to the aminoketone... 

This selectivity for preferred reaction displacing the halide is found withboth P(III) and P(V) mixed halide/ester systems (Equation4.15)38 and has been noted in several patents to be of value for phosphonite synthesis (Equation 4.16).39 40... 

Methyl oxetane-2-carboxylate derivatives (e.g., 284), obtained by ring contraction of aldonolactones, have been employed for the synthesis (279) of the nucleoside / -noroxetanocin [9-(/ -D-eryt/iro-oxetanosyl)adenine, 304] and its a-anomer via an a-chloride obtained by a modified Hunsdiecker reaction. Displacement of chloride by adenine and debenzylation gave 304. The threo isomer of304, /J-epinoroxetanocin (305), was likewise synthesized from D-lyxono-1,4-lactone. The oxetane nucleosides display potent antiviral activity against the human immunodeficiency virus (HIV). 

Many examples of complexes containing enynyl ligands are known from reactions of 1-alkynes with various metal complexes two coordination sites are necessary for this reaction. Displacement of the ligand often results in a catalytic cycle of head-to-head dimerization of the alkyne. The protonation may occur by solvent, e.g., MeOH, in other cases acid is required, e.g., CF3CO2H. Coupling... 

The standard redox potential of the reaction CeS+ + 3e Ce is -2.2336 V. The metal undergoes single replacement reactions, displacing less electropositive metals from their salts in solution or melt ... 

Pyrazines undergo nearly all of the same reactions as pyrimidines, from nucleophilic substitution (SnAt) to palladium-catalyzed cross coupling reactions. Displacement of the chlorides via SnAt reactions with nitrogen (157 158) and sulfur-based nucleophiles (158... 

Chlorinated 2H- pyrimido[l, 2-6 ]pyridazin-2-ones are known to undergo a variety of nucleophilic displacement reactions. Displacement of the chlorine atom in both the 4- and 7-positions of these compounds with methylamine and sodium methanethiolate is facile. Displacement of the chlorine atom in the 3-position does not occur. Therefore, 3,4,7-trichloro-2//-pyrimido[l,2-6]pyridazin-2-one (34) reacts with methanethiol in sodium methoxide to give 3-chloro-4,7-bis(methylthio)-2//-pyrimido[l,2-6]pyridazin-2-one (70) (71JOC3506). 

Tetrabutylammonium fluoride, 286 Titanium(IV) chloride-Diethylalumi-num chloride, 309 Vinylene carbonate, 342 Dihydroxylation (see Addition reactions to carbon-carbon multiple bonds) Dimerization (see Coupling reactions) Displacement reactions (see Substitution reactions)... 

The diisopropylamide anion acts as a base and removes an acidic hydrogen from the carbon adjacent to the carbonyl group. The resulting enolate anion reacts as a nucleophile in an SN2 reaction, displacing the bromine at the primary carbon. 

The first reaction stage is undoubtedly SN2 nucleophilic displacement of chlorine by the ethyl acetoacetate anion. Chlorine bond to carbon is weaker than that of fluorine. The resulting ethyl 5-fluoropentan-2-one-3-carboxylate subsequently cyclizes by an SNi reaction, displacing this time the fluorine atom [73]. 

Considering the thermodynamic parameters of the reaction, it has been determined that the silicic acid with a hexacoordinated atom of silicon H2[Si(OH)6] formed in die process of reaction displaces ammonium ion from phenolates, so that this acid is stronger than catechol. This is in agreement with our experimental data at the beginning of the reaction process the decrease in the pH of the reaction mixture from 7.16 to 5.85 was observed before the pH became constant. 

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