Functional groups, elimination hydrogen

Amorphous metal oxides with basic and amphoteric surfaces are active catalysts for a variety of important reactions including olefin isomerization, hydrogenation, and functional group elimination.2... 

Even so, for polystyrene, benzyl bromide chain ends were preferred over 1-broraoethylbenzene chain ends for cationic initiation. 1-Bromoethylbenzene functional groups possess hydrogens on the B-carbon atom and do not initiate the polymerization entirely by an additive process. The principal side reaction is one of 3-hydrogen elimination (28). 

Functional groups, elimination (s. a. Replacement... by hydrogen) 19, 109 Functionalization... 

The amino functional group is not commonly encountered in steroid synthesis except perhaps in steroidal alkaloids. However, certain elimination reactions have been shown to have theoretical and limited preparative importance, largely due to the efforts of McKenna and co-workers. The Hofmann rule for 2 elimination predicts that alkaline elimination of quaternary ammonium salts will occur towards the carbon carrying the most hydrogen atoms cf. the converse Saytzeff orientation, above). In cyclohexyl systems, the requirement for diaxial elimination appears to be important, as in other 2 eliminations, and the Hofmann rule frequently is not obeyed [e.g., (116) (117)]. 

The hydrogenation step following hydroformylation serves two important purposes. It reduces the aldehyde intermediate product to the desired primary alcohol functional group, which is the primary site of reactivity of the polyol with isocyanates. It also reduces the residual olefins in the FAMEs to saturated hydrocarbons, thus eliminating the pathway to Hock degradation and odor development, which is inherent to other processes that leave fatty acid unsaturation in the polyols. This step eliminates the typical vegetable oil odor from the final namral oil polyols of this process. 

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