Palladium(II)-Catalyzed Regioselective syn-Hydroarylation of Disubstituted Alkynes Using a Removable Directing Group
作者:Zhen Liu、Joseph Derosa、Keary M. Engle
DOI:10.1021/jacs.6b08818
日期:2016.10.5
A palladium(II)-catalyzed regioselective syn-hydroarylation reaction of homopropargyl amines has been developed, wherein selectivity is controlled by a cleavable bidentate directing group. Under the optimized reaction conditions, both dialkyl and alkylaryl alkyne substrates were found to undergo hydroarylation with high selectivity. The products of this reaction contain a 4,4-disubstituted homoallylic
已经开发了钯 (II) 催化的高炔丙基胺的区域选择性顺氢芳基化反应,其中选择性由可裂解的双齿导向基团控制。在优化的反应条件下,发现二烷基和烷芳基炔底物均以高选择性进行加氢芳基化。该反应的产物含有 4,4-二取代的高烯丙基胺基序,这在药物分子和其他生物活性化合物中很常见。
Palladium(II)-Catalyzed Directed <i>anti-</i>Hydrochlorination of Unactivated Alkynes with HCl
作者:Joseph Derosa、Annabelle L. Cantu、Mark N. Boulous、Miriam L. O’Duill、Joshua L. Turnbull、Zhen Liu、Daizy M. De La Torre、Keary M. Engle
DOI:10.1021/jacs.7b00892
日期:2017.4.12
A regioselective anti-hydrochlorination of unactivated alkynes is reported. The reaction utilizes in situ generated HCl as the source of both the Cl- and H+ and is catalyzed by palladium(II) acetate, with loadings as low as 25 ppm. Removable picolinamide and 8-aminoquinoline bidentate directing groups are used to control the regioselectivity of the chloropalladation step and stabilize the resulting
报道了未活化炔烃的区域选择性抗氢氯化作用。该反应利用原位生成的 HCl 作为 Cl- 和 H+ 的来源,并由乙酸钯 (II) 催化,负载量低至 25 ppm。可去除的吡啶甲酰胺和 8-氨基喹啉二齿导向基团用于控制氯钯化步骤的区域选择性,并稳定所得的链烯基钯 (II) 中间体,用于随后的原脱钯反应。该方法提供了以优异的产率和高区域选择性获得广泛的取代链烯基氯的途径。这种转化的产物通过 Stille 偶联成功衍生为多种三取代烯烃产物。进行了反应进程动力学分析,揭示了该催化过程的可能机制。