Reactivity patterns homogeneous reactions

The reactivity patterns of these two reaction types, the formation of C-C and/or of C-heteroatom bonds and the activation of C-C multiple bonds or C-heteroatom multiple bonds, are central to the field. But subsequently, more unique reactivity patterns have been added to the arsenal of homogeneous gold catalysis. 

In fact, under homogenous reaction conditions it was found that the SET mechanism prevailed, affording phenylsulfonyl-derivative 108 as the major product. Similar reactivity patterns were observed in guanidine analogues, with sulfonylation of the 2-NH2 group occurring as the most common side product. 

MAG-10 XRD pattern before and after carbon-coating (22 wt%) in Fig. 5a-b which suggests that the carbon-coating is amorphous. All of these materials are quite thermally stable in a reductive gas environment which allows for propylene gas to be reactively cracked at the surface of these powders resulting in an amorphous carbon film. As suggested by Sandi et al. [23], the propylene gas after reaction tends to leaves a fairly homogenous and hydrogen-free film. 

The reactivity of the molecular fullerene solid resembles the expected pattern for a homogeneous material. Only a small prereactivity at 700 K indicates that a fullcrcne-oxygen complex [12] is formed as an intermediate stoichiometric compound [15, 105], At 723 K the formation of this compound and the complete oxidation are in a steady state [12, 106, 107] with the consequence of a stable rate of oxidation which is nearly independent of the bum-off of the fullerene solid. This solid transforms prior to oxidation into a disordered polymeric material. The process is an example of the alternative reaction scenario sketched above for the graphite oxidation reaction. The simultaneous oxidation of many individual fullerene molecules. leaving behind open cages with radical centers, is the reason for the polymerization. 

In order to parallel solution-phase reactivity and ion-molecule reactions in the gas phase, the reactivity of a typical homogeneous catalyst, described earlier by Grubbs and co-workers [128], was studied by ESMS [129]. Electrospray of the dichloride salt of 15 and increasing the collisional activation potential first yielded predominantly the monocation 16, but with raising the tube lens potential even higher the intensity of 16 decreased due to loss of the second phosphine ligand, loss of trimethylamine, and loss of HCl. The observed fragmentation pattern was consistent with the assumed structure of the ruthenium complex. 

Bimodal patterns are obtained if certain domains within the material, such as crystalline areas, show very low reactivity, and thus remain nearly unaffected, or two competing reaction mechanisms, such as heterogeneous and homogeneous, are followed in parallel. As long as no permethylation is performed, bimodal patterns with a very high substituted fraction, besides a more-randomly substituted one, are formed... 

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