Reactions of alcohol interchange or transesterification method

This method is especially important for the preparation of homologues, which are hardly accessible by other techniques. According to the data of H NMR spectroscopy, the first step of the reaction lies in addition of the free alcohol(andpresumablydestructionoftheexisting [M(OR)Jmoligomers) [196]. There may be two ways to shift the equilibrium in the desired direction distillation of the alcohol with lower boiling point (usually as an azeotrope with 

Apart from alcohols, esters are also used as alkoxylating agents for M(OR) . If the boiling points of the introduced and eliminated alcohols are the same 

In many cases application of esters in contrast to alcohols results in complete substitution of OR-gioups, which (according to Bradley) is due to the stronger coordination of the carbonyl oxygen in comparison with the alkoxide oxygen on the first step of the reaction [196]. Application of esters in the synthesis of trialkylsilanolates is expedient due to their high stability in comparison with RjSiOH, which readily undergoes polymerization and oxidation  

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