Microwave-assisted cycloadditions of 2-alkynylbenzonitriles with sodium azide: selective synthesis of tetrazolo[5,1-a]pyridines and 4,5-disubstituted-2H-1,2,3-triazoles
摘要:
Under microwave irradiation (75 W), treatment of 2-alkynylbenzonitriles with 1.5 equiv of sodium azide in DMSO at 140 degrees C gave 4,5-disubstituted-2H-1,2,3-triazoles in 60-99% yields. Additionally, adding 8 equiv of ZnBr2 and using 8 equiv of sodium azide in DMF at 100 degrees C lead to the formation of tetrazolo[5,1-a]isoquinolines up to 87% yield. (C) 2009 Elsevier Ltd. All rights reserved.
Nickel-Catalyzed Sonogashira C(sp)–C(sp<sup>2</sup>) Coupling through Visible-Light Sensitization
作者:Da-Liang Zhu、Ruijie Xu、Qi Wu、Hai-Yan Li、Jian-Ping Lang、Hong-Xi Li
DOI:10.1021/acs.joc.0c01177
日期:2020.7.17
efficient method for visible-light-initiated, nickel-catalyzed Sonogashira C(sp)–C(sp2) coupling has been developed via an energy-transfer mode. Thioxanthen-9-one as a photosensitizer could significantly accelerate the arylation of alkynes with a wide range of (hetero)aryl halides in high yields. The cross-couplingreaction undergoes the stepwise oxidative addition of an arylhalide to nickel(0), transmetalation
efficient copper-catalyzed radical cascade cyclization strategy was developed, by which a wide variety of 3-sulfonyl substituted indenones were prepared in one pot via reaction of 2-alkynylbenzonitriles with sulfonyl hydrazides in the presence of TBHP and CuI under mild reaction conditions. Much more importantly, the 3-sulfonyl indenones, synthesized through our newly developed copper-catalyzed radical
A lanthanide‐catalyzed intermolecular hydroamination of 2‐alkynylbenzonitriles with secondary amines has been disclosed, providing a streamlined access to a range of aminoisoindoles in moderate to excellent yields. The salient features of this reaction include high bond‐formation efficiency, mild reaction conditions, 100 % atomic efficiency and good functional group tolerance. This methodology has
Microwave-Promoted Copper-Free Sonogashira-Hagihara Couplings of Aryl Imidazolylsulfonates in Water
作者:José F. Cívicos、Diego A. Alonso、Carmen Nájera
DOI:10.1002/adsc.201200629
日期:2013.1.14
Aryl imidazol‐1‐ylsulfonates have been efficiently cross‐coupled with aryl‐, alkyl‐, and silylacetylenes in neat water under copper‐free conditions at 110 °C assisted by microwave irradiation. Using 0.5 mol% of an oxime palladacycle as precatalyst, 2‐dicyclohexylphosphino‐2′,6′‐dimethoxybiphenyl (SPhos, 2 mol%) as ligand, hexadecyltrimethylammonium bromide (CTAB) as additive, and triethylamine (TEA)
We report an efficient approach to synthesize sulfonated indenones via a radical cascade cyclization of 2-alkynylbenzonitriles with sodium arylsulfinates.