Synthesis of 2-substituted 3-chlorobenzofurans <i>via</i> TMSCl-mediated nucleophilic annulation of isatin-derived propargylic alcohols
作者:Zhou Sun、Kuirong Xiang、Hua Tao、Liqun Guo、Ying Li
DOI:10.1039/c8ob01731j
日期:——
A TMSCl-mediated cascade annulation of isatin-derived propargylicalcohols for the synthesis of 2-substituted 3-chlorobenzofurans is now reported. Mechanistic investigations showed that this proceeded through a sequential Meyer–Schuster rearrangement/nucleophilic addition/intramolecular annulation. TMSCl not only acts as a promoter, but also acts as a chlorine source in this protocol.
Rhodium(III)-Catalyzed Cascade Cyclization/Electrophilic Amidation for the Synthesis of 3-Amidoindoles and 3-Amidofurans
作者:Zhiyong Hu、Xiaofeng Tong、Guixia Liu
DOI:10.1021/acs.orglett.6b00689
日期:2016.5.6
A rhodium(III)-catalyzed cascade cyclization/electrophilic amidation using N-pivaloyloxylamides as the electrophilic nitrogen source has been developed. This protocol provides an efficient route for the synthesis of 3-amidoindoles and 3-amidofurans under mild conditions with good functional group tolerance. The synthetic utility of this reaction has been demonstrated through the derivatization of the
Highly Selective and Modular Synthesis of 3-Aryl-4-(arylethynyl)-2<i>H</i>-chromen-2-ones from 2-Iodoaryl 2-Arylacetates through a Carbonylative Sonogashira Coupling-Intramolecular Aldol Cascade Reaction
H-chromen-2-ones from 2-iodoaryl 2-arylacetates and arylacetylenes has been developed. The carbonylative Sonogashira coupling–intramolecular aldol casade reaction was carried out in the presence of Pd(PPh3)2(Cl)2 as the catalyst. The one-pot approach that involves the in situ formation of the 2-iodoaryl 2-arylacetates from the corresponding 2-iodophenols and 2-arylacetyl chlorides followed by the palladium-catalyzed
The synthesis of the bisbenzannelated spiroketal core of natural bioactive rubromycins via a gold-catalyzed double intramolecular hydroalkoxylation was described. A comparative study on the formation of aliphatic and of aromatic spiroketals was also conducted.