Stereoselective synthesis of o-bromo (or iodo)aryl P-chirogenic phosphines based on aryne chemistry.
Stereoselective synthesis of o-bromo (or iodo)aryl P-chirogenic phosphines based on aryne chemistry.
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DOI：
10.1021/jo300910w
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发表时间：
2012-06
期刊：
影响因子：
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通讯作者：
Jérôme Bayardon;Hugo Lauréano;V. Diemer;Mathieu Dutartre;U. Das;Yoann Rousselin;J. Henry;F. Colobert;F. Leroux;S. Jugé
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文献类型：
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作者：
Jérôme Bayardon;Hugo Lauréano;V. Diemer;Mathieu Dutartre;U. Das;Yoann Rousselin;J. Henry;F. Colobert;F. Leroux;S. Jugé
本文报道了含邻溴（或碘）芳基取代基的手性或非手性叔膦的有效合成。该合成的关键步骤是基于仲膦硼烷与1，2-二溴（或二碘）芳烃的反应，由于在正丁基锂存在下原位形成芳炔物种。当使用P-手性仲膦硼烷时，相应的邻卤代芳基膦硼烷不经外消旋而以中等至良好的产率获得，ee高达99%。反应的立体化学，与完全保留的配置在P原子，已建立由X-射线结构的P-手性邻卤代苯基膦硼烷配合物。用DABCO可以很容易地实现硼烷的解络合，而不需要进行外消旋化，从而以高产率获得游离的邻卤代芳基膦。
The efficient synthesis of chiral or achiral tertiary phosphines bearing an o-bromo (or iodo)aryl substituent is described. The key step of this synthesis is based on the reaction of a secondary phosphine borane with the 1,2-dibromo (or diiodo)arene, owing to the formation in situ of an aryne species in the presence of n-butyllithium. When P-chirogenic secondary phosphine boranes were used, the corresponding o-halogeno-arylphosphine boranes were obtained without racemization in moderate to good yields and with ee up to 99%. The stereochemistry of the reaction, with complete retention of the configuration at the P atom, has been established by X-ray structures of P-chirogenic o-halogenophenyl phosphine borane complexes. The decomplexation of the borane was easily achieved without racemization using DABCO to obtain the free o-halogeno-arylphosphines in high yields.