Copper‐Catalyzed Azide–Ynamide Cyclization to Generate α‐Imino Copper Carbenes: Divergent and Enantioselective Access to Polycyclic N‐Heterocycles
作者:Xin Liu、Ze‐Shu Wang、Tong‐Yi Zhai、Chen Luo、Yi‐Ping Zhang、Yang‐Bo Chen、Chao Deng、Rai‐Shung Liu、Long‐Wu Ye
DOI:10.1002/anie.202007206
日期:2020.10.5
Here an efficient copper‐catalyzed cascade cyclization of azide‐ynamides via α‐imino copper carbene intermediates is reported, representing the first generation of α‐imino copper carbenes from alkynes. This protocol enables the practical and divergent synthesis of an array of polycyclic N‐heterocycles in generally good to excellent yields with broad substrate scope and excellent diastereoselectivities
Gold‐Catalyzed Annulations of
<i>N</i>
‐Propargyl Ynamides with Anthranils with Two Distinct Chemoselectivities
作者:Yu‐Chen Hsu、Shu‐An Hsieh、Rai‐Shung Liu
DOI:10.1002/chem.201806083
日期:2019.4.5
Gold‐catalyzedannulation of N‐propargyl ynamides with anthranils can proceed by two distinct mechanisms. In the case of a terminal N‐propargyl ynamide, its resulting α‐imino gold carbene reacts with a tethered alkyne to generate a vinyl cation to enable hydrolysis, which ultimately yields a pyrrolo[2,3‐b]quinoline derivative after treatment with p‐toluenesulfonic acid. For an internal alkyne, its
金催化的N-炔丙基乙酰胺与蒽的环化反应可以通过两种不同的机理进行。在末端N-炔丙基炔基酰胺的情况下,其生成的α-亚氨基金卡宾与链状炔反应生成乙烯基阳离子以实现水解,经p处理后最终生成吡咯并[2,3- b ]喹啉衍生物甲苯磺酸。对于内部炔烃,其α-亚氨基金卡宾通过乙烯基阳离子或烯基金卡宾与链状炔反应。两种途径最终都会导致生成4-酮-2-氨基吡咯衍生物。我们的机理分析表明,对于末端乙酰胺,水是比蒽乙更好的亲核试剂,而水和蒽甲对内部乙酰胺具有同等的反应性。
Generation of Donor/Donor Copper Carbenes through Copper-Catalyzed Diyne Cyclization: Enantioselective and Divergent Synthesis of Chiral Polycyclic Pyrroles
作者:Feng-Lin Hong、Ze-Shu Wang、Dong-Dong Wei、Tong-Yi Zhai、Guo-Cheng Deng、Xin Lu、Rai-Shung Liu、Long-Wu Ye
DOI:10.1021/jacs.9b09303
日期:2019.10.23
yields with wide substratescope and excellent enantioselectivities (up to 97:3 e.r.). Importantly, this protocol represents the first copper-catalyzed asymmetric diyne cyclization. Moreover, mechanisticstudies revealed that the generation of donor/donor copper carbenes is presumably involved in this 1,5-diyne cyclization, which is distinctively different from the related gold catalysis, and thus it constitutes
Enantioselective Synthesis of 5,7-Bicyclic Ring Systems from Axially Chiral Allenes Using a Rh(I)-Catalyzed Cyclocarbonylation Reaction
作者:Francois Grillet、Kay M. Brummond
DOI:10.1021/jo4002432
日期:2013.4.19
pattern of the allene affected the transfer of chiral information. Complete transfer of chirality was obtained for all trisubstitutedallenes, but loss of chiral information was observed for disubstituted allenes. This work constitutes the first demonstration of a transfer of chiral information from an allene to the 5-position of a cyclopentenone using a cyclocarbonylation reaction. The absolute configuration
描述了分子内 Rh(I) 催化的联烯 Pauson–Khand 反应 (APKR) 中的手性转移,以对映选择性地获得四氢甘菊酮、四氢环戊[ c ]氮杂酮和二氢环戊[ c ]氧杂环庚酮 (22-99% ee)。丙二烯的取代模式影响手性信息的传递。所有三取代丙二烯均获得了手性的完全转移,但二取代丙二烯观察到手性信息丢失。这项工作首次证明了利用环羰基化反应将手性信息从丙二烯转移到环戊烯酮的 5 位。相应的环羰基化产物的绝对构型也被确定,这是很少有人做到的。
Copper-catalyzed intermolecular formal [4 + 1] annulation of 1,5-diynes with benzocyclobutenones
作者:Jia-Cheng Li、Tian-Qi Hu、Zhou Xu、Bo Zhou、Long-Wu Ye