Coupling competitive

Figure 5.1. Various adiabatic photochemical reaction mechanisms (see text for details), (a) Simple case of dual fluorescence (b) illumination changes sample (i.e., photochemistry) (c) strong fluorescence quenching (photochemical funnel) (d) competitively coupled product species (e) consecutively coupled product species.

Fig. 10. Different techniques for competitive immuno-polymerase chain reaction of small-molecule compounds. (A) Using biotinylated haptens and a DNA-streptavidin nanocircle conjugate [105], hapten-DNA conjugates were synthesized and used for a competitive assay in a sample containing free hapten and capture antibody-coated surfaces [92]. (B) Hapten-coated microplates were simultaneously incubated with a sample containing free hapten and a hapten-specific antibody. Following competitive coupling, the immobilized antibody was subsequently detected by a species-specific antibody-DNA conjugate [93, 94].

Because of the complex central term representing mobile phase band broadening, Eq. 12.1 has a rather awkward form, not simple to use. The awkwardness reflects the complexity of packed-bed processes, specifically the complexity caused by (i) the many types of velocity states and (ii) the competition (coupling) between diffusion and flow in controlling random displacements. 

ROO-CHD are not formed as the only product of the reaction of R0 2 with phenol indeed, neither under optimum reaction conditions. The competition coupling reactions of phenoxyls described in the Chap. II A. proceed in larger extent also at the molar ratio phenol-to-RO"2 higher than 0.5. 

TABLE 7.1 Catalytic Tests for the Competitive Coupling of Pairs of Amines with one Acid and Pairs of Acids with one Amine Mediated by the Carbodiimide Cationic Condensing Agent in the Presence or Absence of the Hexameric Capsule as Supramolecular Nanoreactor at 60°C, Time 18 h. + Presence Absence... 

FIGURE 7.9 Competitive coupling of a pair of carboxylic adds with a pair of amines mediated by the carbodiimide cationic coupling agent either in the presence or in the absence of the resorcinarene capsule. 

Formation of the dianion and subsequent oxidative homocoupling led to the formation of 122 in a modest 4% yield. The authors attribute the low yield to the fact that there are several competitive coupling pathways. 

Zon, G., Gallo, K. A., Samson, C. J., Shao, K., Summers, M. F., and Byrd, R A. (1985) Analytical studies of mixed sequence oligodeoxyribonucleotides synthesized by competitive coupling of either methyl- or P-cyanoethyl-N,A -diisopropylamino phosphoramidite reagents, including 2 -deoxyinosine Nucl Acids Res. 13,8181-8196. 

In both this and the previous method of preparation, low yields are often found, due to competitive coupling reactions or to further reactions such as the decomposition of the M— R], products. Also tire metal anions are strong nucleophiles and they may cause the or mic halides to undergo elimination reactions. Metal-acyl complexes are often by-products of the reaction of organic halides with the metal carbonyl anions they are formed by insertion reactions (see p. 258). Indeed, acyl halides may be used to give metal-acyl complexes which are dien decarbonylated either thermally or by photochemi techniques [. Some metal-aryl complexes which are... 

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