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。
Asymmetric Hetero-Diels–Alder Reaction of Diazenes Catalyzed by Chiral Silver Phosphate: Water Participates in the Catalysis and Stereocontrol
作者:Bin Liu、Tong-Yu Liu、Shi-Wei Luo、Liu-Zhu Gong
DOI:10.1021/ol503047s
日期:2014.12.5
The chiral silver phosphate was confirmed to efficiently catalyze a highly regio- and enantioselective hetero-Diels–Alder reaction of diazenes to furnish piperazine derivatives in high yields and excellent ee values. DFT calculations revealed that the water molecule participates in the catalysis by coordination to silver phosphate and also found that the hydroxy group of 1-hydroxy-2,3-hexadiene not
2-Markovnikov hydrosilylation of conjugated dienes with primary silanescatalyzed by a quinoline-oxazoline cobalt complex has been described. This protocol provides an efficient approach to chiral allyl dihydrosilanes with high regioselectivity and enantioselectivity (up to 96% ee). The catalyst system is effective for a wide array of conjugated dienes, including mono- and 1,2-disubstituted dienes with aryl
Rhodium Catalyzed Anti-Markovnikov Addition of Triphenylphosphine to 1,3-Dienes A Novel Method to Separate Pure (<i>Z</i>)-1,3-Alkadienes from Isomeric Mixtures
Rhodium-catalyzed addition of triphenylphosphine and trifluoromethanesulfonic acid to (E)-1,3-dienes gives (E)-3-alkenylphosphonium salts in the anti-Markovnikov mode. The addition reactions to (E)-1,3-dienes proceed more rapidly than those to (Z)-1,3-dienes, which can be utilized to separate pure (Z)-1,3-dienes from isomeric mixtures.