Effect of solvent on product

None of these mechanistic proposals is sufficiently general to use to rationalize all of the stereochemical data observed on the hydrogenation of a,[3-unsaturated ketones. By a judicious combination of segments of each of these proposals along with the Horiuti-Polanyi mechanism (2), it is possible, however, to develop a uniform mechanistic rationale that can be useful in determining the effect of solvent on product stereochemistry. In addition, the influence of hydrogen availability, the type and quantity of catalyst, and the nature of other substituents on the reacting molecule on the product isomer distribution can also be more readily understood. 

In the photo sensitized oxygenation reactions of alkenes, not only the influence of the solvent on the reaction rate but also the effect of solvent on product distribution i.e. from competing hydroperoxide, 1,2-dioxetane, and entfo-peroxide formation) is rather small [550, 551],... 

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