SYNTHESIS OF ARYZINC COMPOUNDS AND THEIR APPLICATIONS TO ORGANIC SYNTHESIS

有机锌化合物在很大程度上继续吸引着合成有机化学家，因为如果在它们的进一步转化中观察到它们的高化学选择性和特定的反应活性。在本研究中，我们首次研究了超声波促进芳基卤化物和锌粉直接合成芳基锌化合物。在这种方法中，很容易得到邻位含吸电子基团的芳基锌化合物。在Pd(0)催化剂存在下，锌化合物与芳基卤化物反应，高产率地将锌化合物转化为多官能团的联芳基化合物。这种活化法还可用于邻二碘苯与锌粉的反应，首次生成邻苯二锌化合物。经氯化三甲基锡处理后，该锌化合物被鉴定为相应结构的已知锡化合物。然后，在Pd(0)-催化剂存在下，锌化合物与芳基卤化物或酰基卤化物反应，高产率地转化为对称的邻三苯基或1，2-二酰基苯。除了在Pd(0)络合物中使用三(2，4，6-三甲氧基苯基)膦取代其他磷配体外，与酰基卤化物的选择性单酰化反应也是通过相同的反应完成的。在这些研究中，我们还发现了亲核试剂如卤化物离子、硫氰酸盐离子或N，N-二烷基二硫代氨基甲酸酯离子在NCS的辅助下将金属离子从有机锌化合物中置换出来，从而高产率地合成了各种有机N，N-二烷基二硫代氨基甲酸酯或有机硫氰酸酯。

Organozinc compounds continue to attract synthetic organic chemists to a great extent because if their high chemoselectivity and specific reactivity observed in their further transformations. In this research, we investigated for the first time the direct synthesis of arylzinc compounds from aryl halides and zinc powder promoted by the irradiation of ultrasound. In this method, arylzinc compounds containing electron-withdrawing groups at ortho-positions were obtained readily. The zinc compounds were converted into multi-functional biaryls, which are othewise very difficult to prepare, in high yields by their reaction with aryl halides in the presence of Pd (0)-catalysts.This activation method was also applied to the reaction of o-diiodobenzene with zinc powder, which resulted in the first formation of o-phenylenedizinc compound. After the treatment with chlorotrimethyltin, the zinc compound was identified as the known tin-compound of the corresponding structure. Then, the zinc compound was converted into symmetrical o-terphenyls or 1,2-diacylbenzenes in high yields by the reaction with aryl halides or acyl halides in the presence of Pd (0)-catalyst. Selective monoacylation was also accomplished by the same reaction with acyl halides, except for the use of tris-(2,4,6-trimethoxyphenyl) phosphine in place of other phosphorus ligands in Pd (0) complex.In these studies, we also found the novel displacement of metal ions from organozinc compounds with such nucleophilic reagents as halide ion, thiocyanate ion, or N,N-dialkyldi-thiocarbamate ions by the assistance of NCS.Whereby various organic N,N-dialkyldithio-carbamates or organic thiocyanates were obtained in high yields.