Convergent synthesis
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In [[chemistry]] a '''convergent synthesis''' is a strategy that aims to improve the efficiency of multi-step [[chemical synthesis]]. In '''linear synthesis''' the overall [[chemical yield|yield]] quickly drops with each reaction step:
:A → B → C → D
Suppose the yield is 50% for each reaction, the overall yield of D is only 12.5% from A.
In a convergent synthesis
:A → B (50%)
:C → D (50%)
:B + D → E (25%)
the overall yield of E (25%) looks much better. Convergent synthesis is applied in the synthesis of complex molecules (see [[total synthesis]]) and involve '''fragment coupling''' and '''independent synthesis'''.
Examples:
* Convergent synthesis is encountered in [[dendrimer]] synthesis <ref>Convergent Synthesis of Internally Branched PAMAM Dendrimers Michael Pittelkow, Jrn B. Christensen Org. Lett., 7 (7), 1295 -1298, 2005</ref> where branches (with the number of generations preset) are connected to the central core
* Proteins of up to 300 [[amino acid]]s are produced by a convergent approach using [[chemical ligation]].
* An example of its use in [[total synthesis]] is the final step ([[photochemical]] [2+2][[cycloaddition]]) towards the compound ''Biyouyanagin A'' <ref>''Total Synthesis and Revised Structure of Biyouyanagin'' A [[K. C. Nicolaou]], David Sarlah, and David M. Shaw [[Angew. Chem. Int. Ed.]] '''2007''', 46, 4708 –4711 {{DOI|10.1002/anie.200701552}}</ref>:
:[[Image:BiyouyanaginATotalSynthesis.png|400px|Final step in total synthesis of Biyouyanagin A with acetonaphthone photosensitizer]]
==See also==
*[[divergent synthesis]]
== References ==
{{reflist}}
[[Category:Chemical synthesis]]
[[es:Síntesis convergente]]