'''Claisenova [[kondenzacija]]''' opisuje nastanek vezi [[ogljik]]-[[ogljik]], ki nastane med dvema [[ester|estroma]] ali enim estrom in eno karbonilno spojino ob prisotnosti močne [[bazaBaza (kemija)|baze]]. Primarni produkt je β-keto ester (oz. stabilni [[enolat]] β-keto estra) ali β-diketon.<ref>{{ cite book | first = F. A. | last = Carey | year = 2006 | title = Organic Chemistry | edition = 6th | publisher = McGraw-Hill | location = New York, NY | isbn = 0-07-111562-5 }}</ref> Kondenzacija nosi ime po [[Rainer Ludwig Claisen|Rainerju Ludwigu Claisenu]], ki je prvi objavil svoja dognanja o reakciji leta 1881.<ref>{{ cite journal | author = Claisen, L.; Claparede, A. | title = Condensationen von Ketonen mit Aldehyden | journal = Berichte der Deutschen Chemischen Gesellschaft | year = 1881 | volume = 14 | issue = 2 | pages = 2460–2468 | doi = 10.1002/cber.188101402192 | url = http://gallica.bnf.fr/ark:/12148/bpt6k906939/f871.chemindefer }}</ref><ref>{{ cite journal | author = Claisen, L. | title = Ueber die Einführung von Säureradicalen in Ketone | journal = Berichte der Deutschen Chemischen Gesellschaft | year = 1887 | volume = 20 | issue = 1 | pages = 655–657 | doi = 10.1002/cber.188702001150 }}</ref><ref>{{ cite journal | author = Hauser, C. R.; Hudson, B. E. Jr. | title = The Acetoacetic Ester Condensation and Certain Related Reactions | journal = Organic Reactions | year = 1942 | volume = 1 | doi = 10.1002/0471264180.or001.09 | url = http://www.scribd.com/doc/20632356/Organic-Reactions-v1#page=271 }}</ref>
[[Image:claisen condensation overall.png|700px|center|The overall reaction of the classic Claisen condensation.]]
