For example, epoxidation with peroxy acids is much more widespread than OsO4 oxidation due to the cost and toxicity of the latter. OsO4 is commonly
taught in classes though because it helps teach students to recognize steps in synthesis problems (alkene -> glycol is a common transformation).
Thiourea is strongly preferable to dimethyl sulfide in reductive ozonolysis because of the toxicity of the latter.
Also, the acid-catalyzed hydration of alkenes is not regioselective in any reasonable sense of the word (any hydrolysis-sensitive moiety will be
hydrolysed). Neither is the addition of hydrohalic acids, chlorine or hypochlorite, which are very reactive chemicals (Chlorine will oxidize
benzaldehyde to benzoyl chloride, for example). Ozone and borane also react with many other substrates. In fact the only reaction on the poster which
I would describe as regioselective is oxidation with OsO4, which is one of the few reactions not labeled regioselective. Hydrogenation, treatment with
borohydrides, boranes, etc will affect aldehyde and halide groups along with alkenes.
[Edited on 28-1-2018 by clearly_not_atara] |