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Qualitative assessment of the mechanism

Electrochemical induction of the reaction (Pinson and Saveant, 1974), as shown to occur in a number of cases with aromatic and heteroaromatic substrates (Saveant, 1980a, 1986, 1988), also provides evidence for the Sr I mechanism. The electrochemical approach allows, in addition, a quantitative analysis of the mechanism and reactivity problems and will be described in this connection in the next subsection. [Pg.78]

Stereochemistry has also been used as a diagnostic tool. If an Sr I reaction occurs at an optically active sp carbon centre, racemization should take place. This has indeed been observed in the reaction of 2-(4-nitrophe-nyl)-2-nitrobutanewithbenzenethiolate,benzenesulphinate,2-nitropropanate and also nitrite ions (Kornblum, 1975 Kornblum and Wade, 1987) as well as in the reactions of 2-(4-nitrophenyl)-2-chloroethane with the V,V-diethyl-a-aminopropionitrile and phenlyacetonitrile anions (Cabaret et al., 1985). [Pg.78]


Scope of the reaction 70 Qualitative assessment of the mechanism 75 Quantitative approach to mechanisms and reactivity in the case of aromatic substitution. Termination steps 79 Coupling of aryl radicals with nucleophiles as a concerted electron-transfer-bond-forming reaction 91 Additional remarks 93... [Pg.1]

An initial qualitative assessment of the mechanical strength can made with a simple fingernail test (an acceptable catalyst should not be powderable between the thumbnails) or a simple drop test from a certain height. A quantitative measure of the mechanical strength is the lateral strength of the catalyst particles, which should exceed 15 N cm l... [Pg.25]


See other pages where Qualitative assessment of the mechanism is mentioned: [Pg.75]    [Pg.75]   


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