Primary and Secondary Reactive Species

Oxygen derived primary and secondary reactive species that are important in promoting photo-initiated (and other) AOPs are summarized schematically in Fig. 6-3. 

Examination of equation 5 shows that if there are no chemical reactions, (R = 0), or if R is linear in and uncoupled, then a set of linear, uncoupled differential equations are formed for determining poUutant concentrations. This is the basis of transport models which may be transport only or transport with linear chemistry. Transport models are suitable for studying the effects of sources of CO and primary particulates on air quaUty, but not for studying reactive pollutants such as O, NO2, HNO, and secondary organic species. 

This difference in reactivity between the different classes of amines explains the difference in the primer performance on polyolefin substrates with ethyl cyanoacrylate-based adhesives [37J. Since primary and secondary amines form low molecular weight species, a weak boundary layer would form first, instead of high molecular weight polymer. Also, the polymer, which does ultimately form, has a lower molecular weight, which would lower adhesives strength [8,9]. 

Selectivity and reactivity of mixed anhydrides toward primary and secondary aliphatic and aromatic amines has been studied in details [42, 43] (equation 22) Fluorocarboxyhc acids and then denvahves are used as building blocks m condensa non reactions widi dmucleophihc species for the synthesis of fluoroalkyl-subshtuted lieteroaromahc systems [S 9, 40, 44, 45, 46, 47 4S] (equations 20 21, and 23)... 

The total reaction cross-sections of the individual primary and secondary species were derived and are compared in Table III with reactivities determined from previous electron impact studies (10, 31). 

The polysulfidic moieties of the silanes are unstable, and cleavage of the sulfur groups results in active sulfur species. A notorious problem with this kind of coupling agents is the balance between its reactivity towards the silica, requiring a temperature of at least 130°C to obtain an acceptable speed, and its eagerness to react with the rubber polymer, which starts to become noticeable at temperamres above 145°C. Furthermore, the primary and secondary reactions are chemical... 

Besides the special reactivity of the OH-2, OH-1, and OH-3 groups lies also the classical relative reactivity between the primary and secondary hydroxyl groups. Depending on the reaction conditions and the nature of the electrophilic species, it may be seen that these two types of possible reactivity can direct the reactivity of sucrose. Of course, the product distribution also depends on whether the transformations are kinetically or thermodynamically controlled. For those reactions under kinetic control, if there is enough difference in the rate of the first substitution at the most reactive hydroxyl group and the second one, then the regioselectivity also monitors the degree of substitution. 

The organohaloarsines are very reactive species and are commonly used to prepare heteroleptic tertiary arsines (see Section 2), primary and secondary arsines (see Section 3), and aminoarsines and catenated arsines (see Section 7.3). They easily hydrolyze to their respective arsonous and arsinous acids (equation 27) and are oxidized in air to the corresponding arsonic and arsinic acids (equation 28). 

Two key differences in reactivity between vinyl- or aryl-liftiums and the corresponding R2CuLi species are firstly that the cuprates couple efficiently (and more rapidly than with alkyl halides) with both primary and secondary tosylates, which the lithiums do not, and secondly the general lack of... 

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