I was reading about the acyloin condensation and came across a statemant according to which, the use of TMSCl obviates competing reactions. My question is what kind of competing reaction would happen if it was not used and how? I've read about the possiblity of some sort of Claisen condensation but I fail to see how would that be possible. https://en.wikipedia.org/wiki/Acyloin_condensation
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$\begingroup$ Your acyloin product contains an alcohol under basic conditions this could easily transesterify with starting ester material $\endgroup$ – Waylander Sep 9 '18 at 20:56
The acyloin condensation of diethyl adipate (1) on your Wikipedia citation generates ethoxide that can cause a Dieckmann condensation (intramolecular Claisen condensation, structure 6). TMSCl scavenges ethoxide and silylates the enediolate 3 formed in the acyloin condensation. The process is a 4-electron reduction (see details below). Mild hydrolysis of 4 gives the acyloin 5.
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$\begingroup$ The article by Rühlmann, doi.org/10.1055/s-1971-21707 (German), where this was introduced details this. $\endgroup$ – derek correa Sep 10 '18 at 12:35