Palladium-Catalyzed Carbonylative Coupling of Aryl Iodides and Benzyl Acetylenes to 3-Alkylidenefuran-2-ones under Mild Conditions and Its Density Functional Theory Modeling
A general and efficient method for the palladium‐catalyzed carbonylativecoupling of aryliodides to benzylacetylenes has been developed. Various furanones have been prepared in excellent yields from their corresponding benzylacetylenes at room temperature under a CO atmosphere. For aliphatic alkynes, their corresponding alkynones were obtained in good yields. Detailed DFT calculations have also
Creating Dynamic Nanospaces in Solution by Cationic Cages as Multirole Catalytic Platform for Unconventional C(sp)−H Activation Beyond Enzyme Mimics
作者:Kang Li、Kai Wu、Yu‐Lin Lu、Jing Guo、Peng Hu、Cheng‐Yong Su
DOI:10.1002/anie.202114070
日期:2022.1.26
The generation of permeable porous-cage nanospaces in solution by a highly charged cationic [Pd6(RuL3)8]28+ cage for multirole and multi-way supramolecular catalysis is reported.
Electronic and Steric Effects in the Insertion of Alkynes into an Iridium(III) Hydride
作者:Xingwei Li、Tiffany Vogel、Christopher D. Incarvito、Robert H. Crabtree
DOI:10.1021/om049271z
日期:2005.1.1
relatively electron-rich alkynes (PhC⋮CH, PhCH2C⋮CH, and p-OMeC6H4C⋮CH), double insertion occurs stepwise, each alkyne undergoing rearrangement to a vinylidene intermediate independently to afford an iridium(III) η2-butadienyl. In the first alkyne insertion, deuterium labeling and crossover experiments confirm that the alkyne to vinylidene rearrangement is intraligand. Both a vinyl and a vinylidene intermediate
将多种炔烃插入反式-[IrH(PPh 3)2(C(Ph)CHC(O)Me)(丙酮)] +(1)的Ir-H键中会遵循三种不同的路线,具体取决于炔烃结构。对于相对富电子的炔烃(PhC⋮CH,PhCH 2 C⋮CH和p -OMeC 6 H 4 C⋮CH),分步进行两次插入,每个炔烃独立进行重排成亚乙烯基中间体,得到铱(III) η 2-丁二烯基。在第一次炔烃插入中,氘标记和交叉实验证实炔烃至亚乙烯基的重排是配体内。在第一次插入过程中,乙烯基中间体和亚乙烯基中间体均被捕获并分离。在第二次炔烃插入中,分离出CH有害中间体。贫电子炔烃(p -CF 3 C 6 H 4 C⋮CH和p -NO 2 C 6 H 4 C⋮CH)也经历两次插入1的过程,但使用p -CF 3 C 6 H 4进行氘标记实验C⋮CD表示可逆的C(sp)-H氧化加成。高极化炔烃[R 1 C⋮CC(O)R 2 ]插入1仅发生一次,即使R 1
A Rare η<sup>2</sup>-Butadienyl Complex from an Alkyne Double Insertion with Double Vinylidene Rearrangement
作者:Xingwei Li、Christopher D. Incarvito、Robert H. Crabtree
DOI:10.1021/ja0297281
日期:2003.4.1
A rare eta2-butadienyl Ir(III) complex with a weak Ir...C bond is formed from 1-alkyne double insertion with the independent double alkyne to vinylidene rearrangement. A reaction intermediate is isolated, and labeling and crossover experiments indicate the intramolecularity of both alkyne to vinylidene rearrangements.
Synthesis of (3R,4S)- and (3R,4R)-[4-2H,3H]valine. Preparation of compounds containing chiral methyl groups with an adjacent asymmetric centre
作者:Craig A. Townsend、A. Scott Neese、Alan B. Theis
DOI:10.1039/c39820000116
日期:——
The general problem of the synthesis of compoundscontainingchiralmethylgroupsadjacent to an asymmetric center is addressed for the specific case of valine having such groups exclusively at the 3pro(R) position.