Synthesis of fused and linked bicyclic nitrogen heterocycles by palladium-catalyzed domino cyclization of propargyl bromides.
The palladium(0)-catalyzed direct construction of bicyclic heterocycles is described. Treatment of propargyl bromides that have nucleophilic functional groups connected by two or three carbon atoms with catalytic [Pd(PPh(3))(4)] affords bis-cyclization products in good yields. The desired bicyclic heterocycles can be obtained selectively when using substrates with appropriate nucleophilic groups. We also describe the reaction of a 2-alkynylazetidine derivative with a catalytic amount of [Pd(PPh(3))(4)] under base-free conditions, which affords the same fused heterocycles as the corresponding propargyl bromides.
Okano
Akinori
A
Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.
Tsukamoto
Koji
K
Kosaka
Shohei
S
Maeda
Hatsuo
H
Oishi
Shinya
S
Tanaka
Tetsuaki
T
Fujii
Nobutaka
N
Ohno
Hiroaki
H
D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D003500:Cyclization; D015394:Molecular Structure; D009584:Nitrogen / Q000737:chemistry*; D010165:Palladium / Q000737:chemistry*; D010293:Pargyline / Q000031:analogs & derivatives* / Q000737:chemistry
D019086:Bridged Bicyclo Compounds, Heterocyclic; D010165:Palladium; D010293:Pargyline; C458239:propargyl bromide; D009584:Nitrogen