Catalytic Domino Reaction of Ketones/Aldehydes with Me<sub>3</sub>SiCF<sub>2</sub>Br for the Synthesis of α-Fluoroenones/α-Fluoroenals
作者:Xiaoning Song、Jian Chang、Dongsheng Zhu、Jiaheng Li、Cong Xu、Qun Liu、Mang Wang
DOI:10.1021/acs.orglett.5b00488
日期:2015.4.3
α-fluoroenals is described to undergo the in situ formation of difluorocarbene and silylenolether, difluorocyclopropanation, desilylation, ring-opening, and defluorination sequence. In this tandem reaction, Me3SiCF2Br acts as not only the difluorocarbene source but also the TMS transfer agent as well as internal bromide and fluoride anion catalyst. It allows the transformations to occur smoothly under only
Ring-Opening Diarylation of Siloxydifluorocyclopropanes by Ag(I) Catalysis: Stereoselective Construction of 2-Fluoroallylic Scaffold
作者:Xiaoning Song、Cong Xu、Dongxu Du、Ziming Zhao、Dongsheng Zhu、Mang Wang
DOI:10.1021/acs.orglett.7b03254
日期:2017.12.15
A silver-catalyzed, defluorination ring-opening diarylation of siloxy 2,2-difluorocyclopropanes, with two arenes, to directly prepare polysubstituted 2-fluoroallylic compounds, is described. This multicomponent reaction proceeds smoothly in good stereoselectivity, which is due to a chelation-controlled addition of arenes to α-fluorinated ketone intermediate.
Acetylation of aromatic ethers using acetic anhydride over solid acid catalysts in a solvent-free system. Scope of the reaction for substituted ethers
作者:Keith Smith、Gamal A. El-Hiti、Anthony J. Jayne、Michael Butters
DOI:10.1039/b301260c
日期:2003.4.23
The acetylation of aryl ethers using acetic anhydride in the presence of zeolites under modest conditions in a solvent-free system gave the corresponding para-acetylated products in high yields. The zeolite can be recovered, regenerated and reused to give almost the same yield as that given when fresh zeolite is used.
A General Copper–BINAP-Catalyzed Asymmetric Propargylation of Ketones with Propargyl Boronates
作者:Keith R. Fandrick、Daniel R. Fandrick、Jonathan T. Reeves、Joe Gao、Shengli Ma、Wenjie Li、Heewon Lee、Nelu Grinberg、Bruce Lu、Chris H. Senanayake
DOI:10.1021/ja2028958
日期:2011.7.13
An operationally simple copper-BINAP-catalyzed, highly enantioselective propargylation of ketones is presented. The methodology was developed as an enantioselective process for methyl ethyl ketone and shown to be applicable to a wide variety of prochiral ketones. The resulting homopropargyl adducts are versatile latent carbonyls from which gamma-butyrolactones, beta-hydroxy methyl ketones, and beta-hydroxycarboxylates are readily obtained.