Editing Swern oxidation (section)

==Variations==
When using oxalyl chloride as the [[Dehydration reaction|dehydration]] agent, the reaction must be kept colder than &minus;60&nbsp;°C to avoid side reactions. With [[cyanuric chloride]]<ref>{{cite journal|doi=10.1021/jo015935s | volume=66 | title=A Mild and Efficient Alternative to the Classical Swern Oxidation | journal=The Journal of Organic Chemistry | pages=7907–7909 | author=De Luca Lidia| year=2001 | issue=23 | pmid=11701058 }}</ref> or [[trifluoroacetic anhydride]]<ref>{{cite journal|doi=10.1021/jo00868a012|title=Dimethyl Sulfoxide-Trifluoroacetic Anhydride. New Reagent for Oxidation of Alcohols to Carbonyls|last1=Omura|first1=Kanji|last2=Sharma|first2=Ashok K.|last3=Swern|first3=Daniel|journal=[[J. Org. Chem.]]|year=1976|volume=41|issue=6|pages=957–962}}</ref> instead of oxalyl chloride, the reaction can be warmed to &minus;30&nbsp;°C without side reactions. Other methods for the activation of DMSO to initiate the formation of the key intermediate '''6''' are the use of [[carbodiimides]] ([[Pfitzner–Moffatt oxidation]]), a [[sulfur trioxide pyridine complex]] ([[Parikh–Doering oxidation]]) or [[acetic anhydride]] ([[Albright-Goldman oxidation]]). The intermediate '''4''' can also be prepared from dimethyl sulfide and [[N-Chlorosuccinimide|''N''-chlorosuccinimide]] (the [[Corey–Kim oxidation]]).

In some cases, the use of triethylamine as the base can lead to [[epimerisation]] at the [[alpha and beta carbon|carbon alpha]] to the newly formed carbonyl. Using a [[steric effects|bulkier]] base, such as [[diisopropylethylamine]], can mitigate this side reaction.