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A malonic ester‐type synthesis with 4‐chloroquinoline utilizing highly acidic enols
Author(s) -
Scoville Ann,
Smith Francis X.
Publication year - 1977
Publication title -
journal of heterocyclic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.321
H-Index - 59
eISSN - 1943-5193
pISSN - 0022-152X
DOI - 10.1002/jhet.5570140629
Subject(s) - chemistry , alkyl , quinoline , acetic anhydride , alkylation , protonation , solvent , ring (chemistry) , organic chemistry , medicinal chemistry , enol , catalysis , ion
A synthetic method of attaching carbon‐chain substituents to the 4‐position of the quinoline ring was developed. In our approach enolate anions were generated from highly acidic enols under conditions in which the 4‐chloroquinoline can be N ‐acylated or N ‐protonated. Isopropylidene alkyl(4‐quinolyl)malonates or 5‐alkyl‐5‐(4‐quinolyl)barbituric acids were obtained from the reaction of 4‐chloroquinolines with isopropylidene alkylmalonates in acetic anhydride or with 5‐alkylbarbituric acids by heating in the absence of solvent. Some of the products were hy‐drolyzed and decarboxylated to give the corresponding 4‐alkylated quinolines.