123540-28-3Relevant articles and documents
Lithiation of Methoxypyridines Directed by α-Amino Alkoxides
Comins, Daniel L.,Killpack, Michael O.
, p. 69 - 73 (2007/10/02)
The addition of methoxypyridinecarboxaldehydes to certain lithium dialkylamides gave α-amino alkoxides in situ that were ring-lithiated with alkyllithium bases.Alkylation and hydrolysis on workup provided ring-substituted methoxypyridinecarboxaldehydes via a one-pot reaction.The one-pot methylation of isomeric methoxypyridinecarboxaldehydes was examined.The regioselectivity of the lithiation-methylation was dependent on the aldehyde, the amine component of the α-amino alkoxide, and the metalation conditions.When lithiated N,N,N'-trimethylethylenediamine was used as the amine component of the α-amino alkoxide, methylation generally occured ortho to the aldehyde function.The analogous reactions using lithium N-methylpiperazide as the amine component gave substitution next to the methoxy group.Several new methylated methoxypyridinecarboxaldehydes were prepared in a regioselective manner by using this one-pot procedure.
