Tandem palladium-catalyzed urea arylation-intramolecular ester amidation: regioselective synthesis of 3-alkylated 2,4-quinazolinediones.
o-Halo benzoates can be combined with monoalkyl ureas in a tandem palladium-catalyzed arylation-ester amidation sequence to deliver quinazolinedione products. The reactions are regioselective for formation of the 3-N-alkyl isomers. Significant variation of both coupling partners is possible, allowing the synthesis of a diverse array of substituted quinazolinediones, exemplified by the preparation of a simple unsymmetric-dialkylated natural product. [reaction: see text]
Willis
Michael C
MC
Department of Chemistry, University of Bath, Bath BA2 7AY, United Kingdom. m.c.willis@bath.ac.uk
Snell
Robert H
RH
Fletcher
Anthony J
AJ
Woodward
Robert L
RL
D000473:Alkanes / Q000737:chemistry; D002384:Catalysis; D004952:Esters; D015394:Molecular Structure; D010165:Palladium / Q000737:chemistry*; D052999:Quinazolinones / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism; D014508:Urea / Q000737:chemistry*
D000473:Alkanes; D004952:Esters; D052999:Quinazolinones; D010165:Palladium; D014508:Urea