Synthesis of γ-Benzopyranone by TfOH-Promoted Regioselective Cyclization of o-Alkynoylphenols
摘要:
Regioselective cyclization of o-alkynoylphenols forming gamma-benzopyranones has been demonstrated. Trifluoromethanesulfonic acid (TfOH) induced 6-endo cyclization of o-alkynoylphenols without forming 5-exo cyclized benzofuranone derivatives to provide the corresponding gamma-benzopyranones in high yields.
公开了一种布朗斯台德酸催化的串联工艺,用于获得致密官能化的铬烯基 [3,2- d ] 异恶唑,具有良好至优异的产率和非对映选择性。该程序拟涉及 1,6-共轭加成/亲电加成/双环化炔基邻苯二酚甲基化物 (o -AQMs) 的过程,原位由邻羟基炔丙醇和硝酮生成。温和的条件、良好的官能团相容性、易于放大反应和进一步的产品转化展示了其潜在的应用。
Lewis Acid Catalyzed Tandem 1,4-Conjugate Addition/Cyclization of in Situ Generated Alkynyl <i>o</i>-Quinone Methides and Electron-Rich Phenols: Synthesis of Dioxabicyclo[3.3.1]nonane Skeletons
作者:Ji-Yuan Du、Yan-Hua Ma、Fan-Xiao Meng、Bao-Li Chen、Shao-Liang Zhang、Qian-Li Li、Shu-Wen Gong、Da-Qi Wang、Chun-Lin Ma
DOI:10.1021/acs.orglett.8b01862
日期:2018.7.20
A versatile Lewis acid catalyzed tandem cyclization of in situgenerated alkynyl o-quinone methides (o-AQMs) with electron-rich phenols has been developed on the basis of the mode involving an intermolecular 1,4-conjugate addition/6-endo cyclization/1,3-aryl shift/intramolecular 1,4-conjugate addition cascade. This reaction provides a new method for expeditious assembly of synthetically and biologically
Copper-Catalyzed Dehydrative Cyclization of 1-(2-Hydroxyphenyl)propargyl Alcohols with P(O)H Compounds for the Synthesis of 2-Phosphorylmethylbenzofurans
A tetrakis(acetonitrile)copper(I) hexafluorophosphate [Cu(MeCN)PF6]‐catalyzed dehydrative reaction of 1‐(2‐hydroxyphenyl)propargyl alcohols with diarylphosphine oxides has been developed to provide an efficient synthesis of phosphorylated benzofurans in good to high yields. In the presence of a catalytic amount of an organic base, a variety of H‐phosphonates and H‐phosphinates can also be employed
Palladium‐Catalyzed Desulfitative Cross‐Coupling Reaction of Sodium Sulfinates with Propargylic Carbonates
作者:Anni Qin、Guirong Zhu、Qin Chen、Hui Qian、Shengming Ma
DOI:10.1002/adsc.201900698
日期:2019.10.22
Desulfitative cross‐coupling of propargylic carbonates with sodium sulfinates has been observed. The reaction exhibited good functional group compatibility affording allenes as a single product. Potential anticancer activities of these allene products were also studied.
Synthesis of Sulfonylated Heterocycles via Copper‐Catalyzed Heteroaromatization/Sulfonyl Transfer of Propargylic Alcohols
作者:Xinyi Chen、Andrey Shatskiy、Jian‐Quan Liu、Markus D. Kärkäs、Xiang‐Shan Wang
DOI:10.1002/asia.202001126
日期:2021.1.4
An unprecedented copper‐catalyzed heteroaromatization/sulfonyl transfer of propargylicalcohols with isocyanide has been developed. 3‐Sulfonyl benzofurans and indoles were produced under Cu(I) catalysis in good to high yields. The developed catalytic methodology provides controlled, modular, and facile access to sulfonyl benzoheterocycle scaffolds.
Microwave-Assisted Generation and Capture by Azoles of<i>ortho</i>-Quinone Methide Intermediates under Aqueous Conditions
作者:Silvia González-Pelayo、Luis A. López
DOI:10.1002/ejoc.201701183
日期:2017.11.2
ortho-Quinone methides can be efficiently generated in water. Trapping with azoles provides a convenient route to alkylated azole derivatives, a class of heterocyclic compounds with potential applications in medicinal chemistry. This protocol does not require any activator for the generation of the reactiveintermediate. No chromatographic purification is required in most cases.