Catalysis by boric acid

Fig. 4. The pH-rate profile for the hydration of 2-hydroxypteridine at 20°. Deviations at low rates are due to catalysis by boric acid and bicarbonate ion present in the buffers.

The process starts from tricyclohexylidene triperoxide which is obtained by oxidation of cyclohexanone with hydrogen peroxide. Pyrolysis leads to a mixture of 1,16-hexadecanolide and cyclopentadecane. The latter is oxidized by oxygen under boric acid catalysis to cyclopentadecanol which is subsequently oxidized to cyclopentadecanone [124,124a]. 

With reactive nucleophiles, catalysis by relatively weak acids often suffices, especially with heating. Thus primary and secondary amines have been found to react with a series of 3-alkyloxetane-3-methanols by heating at 120-125 °C in the presence of silica gel, boric acid or cadmium hydroxide (equation 40) (73LA365,74JAP7420071). 

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