Saegusa Oxidation of Enol Ethers at Extremely Low Pd-Catalyst Loadings under Ligand-free and Aqueous Conditions: Insight into the Pd(II)/Cu(II)-Catalyst System
作者:Quan Zhu、Yunsong Luo、Yongyan Guo、Yushun Zhang、Yunhai Tao
DOI:10.1021/acs.joc.0c02987
日期:2021.4.16
system of Saegusa oxidation, which converts enolethers to the corresponding enals with a number of diverse substrates at extremely low catalyst loadings (500 mol ppm) under ligand-free and aqueous conditions, is described. Its synthetic utility was demonstrated by large-scale applications of the catalyst system to important nature molecules. This work allows Saegusa oxidation to become a highly practical
Carbenoid insertion into alkenylzirconocenes—a convergent synthesis of functionalised allylmetallics
作者:Alexander N. Kasatkin、Richard J. Whitby
DOI:10.1016/s0040-4039(00)01024-8
日期:2000.8
Insertion of lithium alkylcarbenoids RC(A)LiX, A= CN, P(O)(OEt)(2), SO2Ph, OMe into alkenylzirconocene chlorides derived by hydrozirconation of terminal alkynes affords functionalised allylzirconium reagents which may be further elaborated. (C) 2000 Elsevier Science Ltd. All rights reserved.
Highly Active Cross-Metathesis of Tetrafluoroethylene with a Seven-Membered N-Heterocyclic-Carbene–Ruthenium Catalyst
A drastic increase in catalyst turnover number (TON) was accomplished in the cross-metathesis of tetrafluoroethylene (TFE) and vinyl ethers. Under a continuous flow of TFE, catalyst Ru7, which contains a seven-membered N-heterocyclic carbene (NHC) ligand, reached a TON of 4100; this is 2 orders of magnitude higher than the highest hitherto reported value. Mechanistic studies revealed that the expanded
Reaction of peroxyacetals with silyl ketene acetals: synthesis of 3-peroxyalkanoates and 3-peroxyalkanals
作者:P.H Dussault、R.J Lee、J.A Schultz、Y.S Suh
DOI:10.1016/s0040-4039(00)00914-x
日期:2000.7
Lewis acid-mediated reaction of monoperoxyacetals with silylketeneacetals (SKAs) provides an efficient approach to 3-peroxyalkanoates. Propionate SKAs react with aliphatic peroxyacetals to furnish 3-peroxy-2-methyl alkanoates with modest anti-selectivity. Although acetate and thioacetate SKAs are less reactive, the latter react with unsaturated peroxyacetals to furnish peroxyalkenoates and -alkadienoates