Exploitation of differential reactivity of the carbon–chlorine bonds in 1,3-dichloroisoquinoline. Routes to new N,N-chelate ligands and 1,3-disubstituted isoquinolines
Exploitation of differential reactivity of the carbon–chlorine bonds in 1,3-dichloroisoquinoline. Routes to new N,N-chelate ligands and 1,3-disubstituted isoquinolines
Exploitation of differential reactivity of the carbon–chlorine bonds in 1,3-dichloroisoquinoline. Routes to new N,N-chelate ligands and 1,3-disubstituted isoquinolines
作者:Alan Ford、Ekkehard Sinn、Simon Woodward
DOI:10.1039/a605827b
日期:——
Under Pd(PPh3)4 catalysis, coupling of
arylboronic acids to the 1-position of 1,3-dichloroisoquinoline takes
place, leading exclusively to 1-aryl-3-chloroisoquinolines. This
regiochemistry is demonstrated by the crystal structure of
3-chloro-1-(8-methoxy-1-naphthyl)isoquinoline. The 3-chloro group may be
modified by nickel-catalysed reaction with Grignard reagents or direct
nucleophilic displacement with LiSCH2Ph. Attempted lithiation
of the 3-position is not successful (either deprotonation or complex
reactivity results). Under zinc reduction in the presence of
NiCl2âPPh3 and NaI, the
1-aryl-3-chloroisoquinolines furnish 3,3â²-biisoquinolines in good
yield.