Copper-catalyzed amination of potassium aryl trifluoroborates using aqueous ammonia
作者:André P. Liesen、Arisson T. Silva、jokderléa C. Sousa、Paulo H. Menezes、Roberta A. Oliveira
DOI:10.1016/j.tetlet.2012.06.011
日期:2012.8
The conversion of potassium aryl trifluoroborates containing different functionalities into the corresponding aryl amines using a catalytic amount of CuSO4·5H2O is described. The methodology uses water as a solvent under aerobic conditions to give the products in good yields.
<sup>1</sup>
H, <sup>13</sup>
C, <sup>19</sup>
F and <sup>11</sup>
B NMR spectral reference data of some potassium organotrifluoroborates
作者:Roberta A. Oliveira、Ricardo O. Silva、Gary A. Molander、Paulo H. Menezes
DOI:10.1002/mrc.2467
日期:2009.10
Complete (1)H, (13)C, (19)F and (11)BNMRspectraldata for 28 potassiumorganotrifluoroborates are described. The resonance for the carbon bearing the boron atom is described for most of the studied compounds. A modified (11)BNMR pulse sequence was used and better resolution was observed allowing the observation of (11)B-(19)F coupling constants for some of the studied compounds.
Efficient cross-coupling, allowing a straightforward access to congested benzophenones, between aromatic aldehydes and potassium aryltrifluoroborates, is described in the presence of a rhodium/tri-tert-butylphosphane catalyst system and acetone as cosolvent. The use of the stable phosphonium salts of tri-tert-butylphosphane prevented the use of highly oxidizable tri-tert-butylphosphane and allowed
Efficient Hydrolysis of Organotrifluoroborates via Silica Gel and Water
作者:Gary A. Molander、Livia N. Cavalcanti、Belgin Canturk、Po-Shen Pan、Lauren E. Kennedy
DOI:10.1021/jo901441u
日期:2009.10.2
and efficient method for the hydrolysis of organotrifluoroborates to unveil boronic acids using silicagel and H2O was developed. This method proved to be tolerant of a broad range of aryl-, heteroaryl-, alkenyl-, and alkyltrifluoroborates as well as structurally diverse aminomethylated organotrifluoroborates. As anticipated, electron-rich substrates provided the corresponding boronic acids more readily
开发了一种使用硅胶和 H 2 O水解有机三氟硼酸盐以揭示硼酸的通用、温和且有效的方法。事实证明,该方法可以耐受各种芳基-、杂芳基-、烯基-和烷基三氟硼酸盐以及结构多样的氨甲基化有机三氟硼酸盐。正如预期的那样,由于共振稳定的二氟硼烷中间体,富电子底物比缺电子底物更容易提供相应的硼酸。开发的方法进一步扩展用于将有机三氟硼酸盐转化为相应的硼酸酯。
Scope of the Palladium-Catalyzed Aryl Borylation Utilizing Bis-Boronic Acid
作者:Gary A. Molander、Sarah L. J. Trice、Steven M. Kennedy、Spencer D. Dreher、Matthew T. Tudge
DOI:10.1021/ja303181m
日期:2012.7.18
wasteful reagents to prepare boronic acid derivatives and require additional steps to afford the desired boronic acid. The scope of the previously reported palladium-catalyzed, direct boronic acid synthesis is unveiled, which includes a wide array of synthetically useful aryl electrophiles. It makes use of the newly available second generation Buchwald XPhos preformed palladium catalyst and bis-boronic