Potassium <i>tert</i>-Butoxide Promoted Intramolecular Arylation via a Radical Pathway
作者:Daniela Sustac Roman、Yoko Takahashi、André B. Charette
DOI:10.1021/ol201160s
日期:2011.6.17
Potassium tert-butoxide mediated intramolecular cyclization of aryl ethers, amines, and amides was efficiently performed under microwave irradiation to provide the corresponding products in high regioisomeric ratios. The reaction proceeds via single-electron transfer to initiate the formation of an arylradical, followed by a kinetically favored 5-exo-trig and subsequent ring expansion.
Cycloisomerization of Carbamoyl Chlorides in Hexafluoroisopropanol: Stereoselective Synthesis of Chlorinated Methylene Oxindoles and Quinolinones
作者:José F. Rodríguez、Anji Zhang、Jonathan Bajohr、Andrew Whyte、Bijan Mirabi、Mark Lautens
DOI:10.1002/anie.202103323
日期:2021.8.16
chloroacylation of alkyne-tethered carbamoyl chlorides. This reaction avoids the use of a metal catalyst and accesses products in high yields and stereoselectivities. Additionally, this reaction is scalable and proved amenable to a series of product derivatizations, including the synthesis of nintedanib. The reactivity of alkene-tethered carbamoyl chlorides with hexafluoroisopropanol (HFIP) was harnessed
One-pot strategy of copper-catalyzed synthesis of 1,2-disubstituted benzimidazoles
作者:Caixia Xie、Xushuang Han、Jian Gong、Danyang Li、Chen Ma
DOI:10.1039/c7ob00945c
日期:——
A simple, one-pot and copper-catalyzed coupling reaction for the construction of 1,2-disubstituted benzimidazole derivatives is described. Low-cost copper salt and weak base K3PO4 were utlized in this reaction. A variety of 1,2-disubstituted benzimidazoles were obtained in moderate to excellent yields.
An efficientapproach to the synthesis of benzimidazole derivatives has been achieved by copper-catalyzed double C–N bonds formation of N-alkyl-2-iodoaniline and sodium azide. The reaction was supposed to proceed throughcopper-catalyzed tandem reaction of SNAr reaction, aerobic oxidation of C(sp3)–H bond and intramolecular C–N bond formation sequence. Structurally diverse 2-aryl, alkenyl and alkyl
Single Bifunctional Ruthenium Catalyst for One-Pot Cyclization and Hydration giving Functionalized Indoles and Benzofurans
作者:Reji N. Nair、Paul J. Lee、Arnold L. Rheingold、Douglas B. Grotjahn
DOI:10.1002/chem.201001075
日期:2010.7.19
Bifunctional is more than twice as fun! At low loading, catalyst 1 (see scheme) can form two important heterocycle classes, apparently by attack of XH on a vinylidene intermediate. Aza‐ and nitroindoles can be formed, and all N‐protecting groups tested (alkyl, allyl, sulfonyl) were tolerated. The newly formed ring can be deuterated in one step, and for substrates with two terminal alkynes, cyclization