Rieche formylation
{{Short description|Chemical reaction}}
{{Use dmy dates|date=March 2024}}
{{Reactionbox
| Name = Rieche formylation
| NamedAfter = Alfred Rieche
| Type = Substitution reaction
}}
Rieche formylation is a type of formylation reaction. The substrates are electron rich aromatic compounds, such as mesitylene{{cite journal|last1=Rieche|first1=A.|last2=Gross|first2=H.|last3=Höft|first3=E.|title=Aromatic Aldehydes. Mesitaldehyde|journal=Organic Syntheses|date=1967|volume=47|issue=47|page=1|doi=10.15227/orgsyn.047.0001}} or phenols,{{cite journal|last1=García|first1=Oscar|last2=Nicolás|first2=Ernesto|last3=Albericio|first3=Fernando|title=o-Formylation of electron-rich phenols with dichloromethyl methyl ether and TiCl4|journal=Tetrahedron Letters|date=June 2003|volume=44|issue=27|pages=4961–4963|doi=10.1016/S0040-4039(03)01168-7}} with dichloromethyl methyl ether acting as the formyl source. The catalyst is titanium tetrachloride and the workup is acidic. The reaction is named after Alfred Rieche who discovered it in 1960.{{cite journal|last1=Rieche|first1=Alfred|last2=Gross|first2=Hans|last3=Höft|first3=Eugen|title=Über α-Halogenäther, IV. Synthesen aromatischer Aldehyde mit Dichlormethyl-alkyläthern|journal=Chemische Berichte|date=January 1960|volume=93|issue=1|pages=88–94|doi=10.1002/cber.19600930115}}
