Convergent synthesis 1702177 186630223 2008-01-24T18:05:36Z V8rik 195918 /* External links */ rm spam link: no specific content on Convergent synthesis 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]]