N. Sumida et al., Conversion of aldehydes into geminal dicarboxylates (acylals) catalyzed bylithium tetrafluoroborate, SYNLETT, (12), 2001, pp. 1921-1922
A variety of aldehydes react with acid anhydrides in the presence of a cata
lytic amount of lithium tetrafluoroborate to afford the corresponding gemin
al dicarboxylates (acylals) in good to excellent yields.