%0 Journal Article
%T Iminium Salts by Meerwein Alkylation of Ehrlich¡¯s Aldehyde
%A Carmen Froschauer
%A Hedda K. Weber
%A Volker Kahlenberg
%A Gerhard Laus
%A Herwig Schottenberger
%J Crystals
%D 2013
%I MDPI AG
%R 10.3390/cryst3010248
%X 4-(Dimethylamino)benzaldehyde is alkylated at the N atom by dialkyl sulfates, MeI, or Me 3O BF 4. In contrast, ethylation by Et 3O BF 4 occurs selectively at the O atom yielding a quinoid iminium ion. 4-(Diethylamino)benzaldehyde is alkylated only at O by either Et or Me oxonium reagent. The iminium salts are prone to hydrolysis giving the corresponding hydrotetrafluoroborates. Five crystal structures were determined.
%K alkylation
%K Ehrlich¡¯s aldehyde
%K iminium salt
%K quinoid
%K quinone
%U http://www.mdpi.com/2073-4352/3/1/248