Metal-free intermolecular cyclopropanation between alkenes and iodonium ylides mediated by PhI(OAc)<sub>2</sub>·Bu<sub>4</sub>NI
作者:Jason Tao、Carl D. Estrada、Graham K. Murphy
DOI:10.1039/c7cc04859a
日期:——
A rapid, mild and metal-freeintermolecular cyclopropanation between iodonium ylides and alkene-containing substrates mediated by PhI(OAc)2·Bu4NI is reported. Iodonium ylides of cyclic and acyclic 1,3-dicarbonyls were reacted with a variety of mono-, di-, tri- and tetra-substituted alkenes of various structural types to give 29 cyclopropanes in up to 97% yield.
Enantioselective Michael/Cyclization Reaction Sequence: Scaffold-Inspired Synthesis of Spirooxindoles with Multiple Stereocenters
作者:Yiming Cao、Xianxing Jiang、Luping Liu、Fangfang Shen、Futing Zhang、Rui Wang
DOI:10.1002/anie.201104216
日期:2011.9.19
A‐spiro‐ing: The title reaction of α‐isothiocyanato imides and methyleneindolinones has been realized for the first time using 1 as the catalyst. This newly developed synthetic method provides a simple, efficient, and environmentally friendly way to access, in an enantioselective manner, densely functionalized spirooxindoles having three contiguous stereogenic centers.
Combining cycloisomerization with trienamine catalysis: a regiochemically flexible enantio- and diastereoselective synthesis of hexahydroindoles
作者:V. Chintalapudi、E. A. Galvin、R. L. Greenaway、E. A. Anderson
DOI:10.1039/c5cc08886k
日期:——
The synthesis of polysubstituted hexahydroindoles through trienamine-organocatalyzed cycloadditions of pyrrolidinyl dienals, prepared by palladium-catalyzed cycloisomerization, is reported.
The Wittig reaction of benzofuran-2, 3-diones (2), cyclic α-ketoesters, was examined. The reaction of 2 having an electron-donating substituent on the aromatic ring with a stable ylide afforded not 3-alkylidene-2(3H)-benzofuranones (4) but 2-alkylidene-3(2H)-benzofuranones (1) with high regioselectivity.