one-pot synthesis
{{Short description|Chemical synthesis strategy}}
{{Redirect|One-pot|one-pot meals|Stew}}
File:Hydroxyquinoline synthesis.svg
In chemistry a one-pot synthesis is a strategy to improve the efficiency of a chemical reaction in which a reactant is subjected to successive chemical reactions in just one reactor. This is much desired by chemists because avoiding a lengthy separation process and purification of the intermediate chemical compounds can save time and resources while increasing chemical yield.
An example of a one-pot synthesis is the total synthesis of tropinone or the Gassman indole synthesis. Sequential one-pot syntheses can be used to generate even complex targets with multiple stereocentres, such as oseltamivir,{{Cite journal
| last1 = Ishikawa | first1 = H.
| last2 = Suzuki | first2 = T.
| last3 = Hayashi | first3 = Y.
| title = High-yielding synthesis of the anti-influenza neuramidase inhibitor (-)-oseltamivir by three "one-pot" operations
| journal = Angewandte Chemie International Edition in English
| volume = 48
| issue = 7
| pages = 1304–1307
| year = 2009
| pmid = 19123206
| doi = 10.1002/anie.200804883
}} which may significantly shorten the number of steps required overall and have important commercial implications.
A sequential one-pot synthesis with reagents added to a reactor one at a time and without work-up is also called a telescoping synthesis.
In one such procedure{{Cite journal| last1 = Cameron | first1 = M.| last2 = Hoerrner | first2 = R. S.| last3 = McNamara| last4 = Figus| last5 = Thomas| title = One-Pot Preparation of 7-Hydroxyquinoline| journal = Organic Process Research & Development| volume = 10| issue = 1| pages = 149| year = 2006| doi = 10.1021/op0501545 | first3 = J. M. | first4 = M. | first5 = S. }} the reaction of 3-N-tosylaminophenol I with acrolein II affords a hydroxyl substituted quinoline III through 4 sequential steps without workup of the intermediate products (see image). The addition of acrolein (blue) is a Michael reaction catalyzed by N,N-diisopropylamine, the presence of ethanol converts the aldehyde group to an acetal but this process is reversed when hydrochloric acid is introduced (red). The enolate reacts as an electrophile in a Friedel-Crafts reaction with ring-closure. The alcohol group is eliminated in presence of potassium hydroxide (green) and when in the final step the reaction medium is neutralized to pH 7 (magenta) the tosyl group is eliminated as well.