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.
在Pd(PPh3)4催化下,苯硼酸与1,3-二氯异喹啉的1位发生偶联反应,形成唯一产物1-芳基-3-氯异喹啉。这种区域化学性质通过3-氯-1-(8-甲氧基-1-萘基)异喹啉的晶体结构得以证明。3-氯基团可通过镍催化的与格氏试剂反应或直接与LiSCH2Ph发生亲核取代反应进行修饰。尝试对3位进行锂化反应未能成功(无论是脱质子化还是复杂反应结果)。在NiCl2•PPh3和NaI存在的条件下,以锌还原1-芳基-3-氯异喹啉,可获得高产率的3,3′-双异喹啉。