- Synthon
A synthon is a concept in
retrosynthetic analysis . It is defined as a structural unit within amolecule which is related to a possible synthetic operation. The term was coined byE.J. Corey . It is noted [Organic Synthesis, the science behind the art. W.A. Smit, A.F. Buchkov, R.Cople, Royal Society of Chemistry ISBN 0-85404-544-9 ] that the phrase does not feature very prominently in Corey's book, "The Logic of Chemical Synthesis", as it is not included in the index.Example
In planning the synthesis of
phenylacetic acid , two synthons are identified: a nucleophilic "-COOH" group, and an electrophilic "PhCH2+" group. Of course, both synthons do not exist per se; synthetic equivalents corresponding to the synthons are reacted to produce the desired product. In this case, thecyanide anion is the synthetic equivalent for the -COOH synthon, whilebenzyl bromide is the synthetic equivalent for the benzyl synthon.The synthesis of phenylacetic acid determined by retrosynthetic analysis is thus:
# PhCH2Br + NaCN → PhCH2CN + NaBr
# PhCH2CN + 2 H2O → PhCH2COOH + NH3Common synthons
* C1 synthons -
carbon dioxide ,carbon monoxide ,cyanide
* C2 synthons -acetylene ,acetaldehyde
* -C2H4OH synthon -ethylene oxide
*carbocation synthons -alkyl halides
*carbanion synthons -Grignard reagent s,organolithium s, substituted acetylidesReferences
Wikimedia Foundation. 2010.