Iminium Salts by Meerwein Alkylation of Ehrlich’s Aldehyde

Iminium Salts by Meerwein Alkylation of Ehrlich’s Aldehyde

4-(Dimethylamino)benzaldehyde is alkylated at the N atom by dialkyl sulfates, MeI, or Me3O BF4. In contrast, ethylation by Et3O BF4 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 structu...

Chemistry of Iminium Salts and Related Compounds

Chemistry of Iminium Salts and Related Compounds

Chemistry of Iminium Salts, Imines, and Related Compounds

Zeolite catalyzed alkylation of toluene by alcohol

Vapor-phase methylation of toluene using methanol and its isopropylation with 2-propanol has been investigated ina down flow reactor under atmospheric conditions using N2 carrier over a series of surface modified andunmodified ZSM-5 (Si/Al= 60-170) loaded with H3PO4, differing in the external surface treatment of the zeolites.The feed molar ratios of toluene/methanol and toluene/2-propanol were...