Enantioselective Synthesis of Functionalized Arenes by Nickel‐Catalyzed Site‐Selective Hydroarylation of 1,3‐Dienes with Aryl Boronates
作者:Justin S. Marcum、Tiffany R. Taylor、Simon J. Meek
DOI:10.1002/anie.202004982
日期:2020.8.10
A catalytic method for the site‐selective and enantioselective synthesis of functionalized arenes by the intermolecular hydroarylation of terminal and internal 1,3‐dienes with aryl pinacolato boronates is reported. The reactions are promoted by 5.0 mol % of a readily available monodentate phosphoramidite‐Ni complex in ethanol, affording a variety of enantioenriched products in up to 96 % yield and
Catalytic (3+2) Palladium‐Aminoallyl Cycloaddition with Conjugated Dienes
作者:Barry M. Trost、Zhongxing Huang
DOI:10.1002/anie.201900693
日期:2019.5.6
application of tailored aminoallyl precursors for catalytic (3+2) cycloaddition with conjugateddienes via a Pd‐aminoallyl intermediate. The new cycloaddition reactions override the conventional (4+3) selectivity of aminoallyl cation cycloaddition through a sequence of Pd‐allyl transfer and ring closure. A variety of highly substituted or fused pyrrolidine rings were synthesized using the cycloaddition, and can
Transition metal-catalyzed dehydrogenation is a clean oxidation method requiring no additional oxidants. We have accomplished a heterogeneous Pd/C-catalyzed aqueous dehydrogenation of 1,4-cyclohexadienes and cyclohexenes to give the corresponding highly-functionalized arenes. Furthermore, various arenes could be efficiently constructed in a one-pot manner via a Diels–Alder reaction and the following
Chemoselective Borane‐Catalyzed Hydroarylation of 1,3‐Dienes with Phenols
作者:Guoqiang Wang、Liuzhou Gao、Hui Chen、Xueting Liu、Jia Cao、Shengda Chen、Xu Cheng、Shuhua Li
DOI:10.1002/anie.201811729
日期:2019.2.4
with various phenols has been established through a combination of theoretical and experimentalinvestigations, affording structurally diverse ortho‐allyl phenols. DFT calculations show that the reaction proceeds through a borane‐promoted protonation/Friedel–Crafts pathway involving a π‐complex of a carbocation–anion contactionpair. This protocol features simple and mild reaction conditions, broad
通过理论和实验研究相结合,已经建立了由AB(C 6 F 5)3催化的一系列1,3-二烯与各种酚的加氢芳基化反应,从而提供了结构多样的邻烯丙基苯酚。DFT计算表明,反应是通过硼烷促进的质子化/ Friedel-Crafts途径进行的,该途径涉及碳正离子-阴离子接触离子对的π-络合物。该方案具有简单温和的反应条件,宽泛的官能团耐受性和低催化剂负载量。将所得的邻-烯丙基苯酚可进一步转化为使用B(C黄烷衍生物6 ˚F 5)3具有良好的顺式非对映选择性。此外,这种转化被应用于药物化合物的后期修饰。
Copper-catalyzed pyrrole synthesis from 3,6-dihydro-1,2-oxazines
Highly-functionalized pyrroles could be effectively synthesized from 3,6-dihydro-1,2-oxazines using a heterogeneous copper on carbon (Cu/C) under neat heating conditions. Furthermore, the in situ formation of 3,6-dihydro-1,2-oxazines via the hetero Diels–Alder reaction between nitroso dienophiles and 1,3-dienes and the following Cu/C-catalyzed pyrrolesynthesis also provided the corresponding pyrrole derivatives