作者:Jeffery M. Atkins、Edwin Vedejs
DOI:10.1021/ol051244x
日期:2005.7.1
[reaction: see text]. Methodology has been developed to prepare bis-oxazoles via a two-stage iterative process. The sequence begins with C(2)-chlorination of a lithiated oxazole using hexachloroethane. Generation of the C(2)-C(4)(') bond by S(N)Ar substitution with TosMIC anion, followed by conversion to the heterocycle in a one-pot reaction with glyoxylic acid monohydrate, affords the desired bis-oxazole
[反应:请参见文字]。已经开发了通过两步迭代过程制备双恶唑的方法。该序列开始于使用六氯乙烷对锂化的恶唑进行C(2)氯化反应。通过用TosMIC阴离子进行S(N)Ar取代生成C(2)-C(4)(')键,然后在与乙醛酸一水合物的一锅反应中转化为杂环,得到所需的双恶唑收率和纯度都很高。两步法可以有效合成三恶唑和第一种迭代制备的四恶唑。