Electrostatic Control of Regioselectivity in Au(I)-Catalyzed Hydroarylation
作者:Vivian M. Lau、William C. Pfalzgraff、Thomas E. Markland、Matthew W. Kanan
DOI:10.1021/jacs.6b11971
日期:2017.3.22
states. Here we investigate the effects of ion pairing on the regioselectivity of the hydroarylation of 3-substituted phenyl propargyl ethers catalyzed by cationic Au(I) complexes, which forms a mixture of 5- and 7-substituted 2H-chromenes. We show that changing the solvent dielectric to enforce ion pairing to a SbF6- counterion changes the regioselectivity by up to a factor of 12 depending on the substrate
Coupling of 2<i>H</i>-Chromenes with Silyl Ketene Acetals Enabled by Borane Catalysis
作者:Xin-Shen Liang、Rui-Dong Li、Wei Sun、Zhong Liu、Xiao-Chen Wang
DOI:10.1021/acscatal.2c02774
日期:2022.8.5
unknown in the literature. Herein, we report that this activity was observed with 2H-chromenes and the catalytic C(sp3)–H functionalization reaction based on this activity was established by using silylketeneacetals as the nucleophiles.
The Thermal [3,3] Claisen Rearrangement of the 3-Substituted Phenyl Allyl and Propargyl Ethers. The Synthesis of 4-Halobenzo[b]furans
作者:Vernon G. S. Box、Panayiotis C. Meleties
DOI:10.3987/rev-98-501
日期:——
Catalytic Asymmetric Cross-Dehydrogenative Coupling of 2<i>H</i>
-Chromenes and Aldehydes
作者:Xinhui Pan、Xigong Liu、Shutao Sun、Zhilin Meng、Lei Liu
DOI:10.1002/cjoc.201800369
日期:2018.12
The first catalyticasymmetric cross‐dehydrogenative coupling of 2H‐chromenes with aldehydes using o‐chloranil (3,4,5,6‐tetrachloro‐1,2‐ benzoquinone) as an oxidant has been described. The organocatalytic process is tolerated with a broad range of structurally and electronically varied 2H‐chromenes and aldehydes with good yield and high enantiocontrol.
Synthesis of 2<i>H</i>-Chromenes via Hydrazine-Catalyzed Ring-Closing Carbonyl-Olefin Metathesis
作者:Yunfei Zhang、Janis Jermaks、Samantha N. MacMillan、Tristan H. Lambert
DOI:10.1021/acscatal.9b03656
日期:2019.10.4
The catalytic ring-closing carbonyl-olefin metathesis (RCCOM) of O-allyl salicylaldehydes to form 2H-chromenes is described. The method utilizes a [2.2.1]-bicyclic hydrazine catalyst and operates via a [3 + 2]/retro-[3 + 2] metathesis manifold. The nature of the allyl substitution pattern was found to be crucial, with sterically demanding groups such as adamantylidene or diethylidene offering optimal