Reactivity of indole-3-alkoxides in the absence of acids: Rapid synthesis of homo-bisindolylmethanes
作者:Bhavani Shankar Chinta、Beeraiah Baire
DOI:10.1016/j.tet.2016.10.067
日期:2016.12
properties of the alkoxides offered the direct and selective construction of bisindolylmethanes and indole-3-carbinols. This process shows very broad scope and represents the reagent (external) free, greener synthesis of structurally divergent bisindolylmethanes.
A Route to Polysubstituted Aziridines from Carbenes and Imines through a Nondiazo Approach
作者:Hejiang Luo、Kai Chen、Huanfeng Jiang、Shifa Zhu
DOI:10.1021/acs.orglett.6b02429
日期:2016.10.21
for the synthesis of polysubstituted aziridines utilizing enynones and imines is described. This transformation is achieved through the reaction of imines with donor/donor carbene intermediates, which were generated in situ from the cyclization of enynones. Furthermore, the resulted aziridines were good 1,3-dipoles, which could be efficiently trapped by dipolarophiles to give five-membered heterocycles
1,2-Oxazol derivatives 3 were prepared by a highly regioselective 1,3-dipolar cycloaddition of nitrileoxides and α,β-acetylenicaldehydes 1 in good yields. Reactive nitrileoxides were generated in situ from stable chloro-oxime reagents 2 and triethyl amine. The cycloaddition reaction showed broad substrate scope and good functional group compatibility.
NHC-catalyzed enantioselective C2-functionalization of 3-hydroxychromenones <i>via</i> α,β-unsaturated acyl azoliums
作者:Krzysztof Dzieszkowski、Michał Słotwiński、Katarzyna Rafińska、Tadeusz M. Muzioł、Zbigniew Rafiński
DOI:10.1039/d1cc03708k
日期:——
A novel synthetic method for enantioselective C2-functionalization of 3-hydroxychromenones promoted by N-heterocyclic carbenes via the formation of α,β-unsaturatedacylazolium intermediates, which occurs with Coates–Claisen rearrangement is established. This synthetic strategy enabled the rapid assembly of enantiomerically enriched δ-hydroxychromenone-derived esters/amides under mild conditions with
Gold‐Catalyzed Synthesis of 2,5‐Disubstituted Oxazoles from Carboxamides and Propynals
作者:Yun Xu、Qian Wang、Yufeng Wu、Zhongyi Zeng、Matthias Rudolph、A. Stephen K. Hashmi
DOI:10.1002/adsc.201801386
日期:2019.5.14
synthesized by oxidative gold catalysis. In contrast to a reported procedure that delivers 2,4‐disubstituted oxazoles starting from terminal alkynes, a switch in selectivity towards a 2,5‐disubstitution is achieved by the use of propynals as starting materials. In the newreaction, the key intermediate is formed by the nucleophilic attack of the carboxamide onto a gold carbenoid, and then condensates with