Benziodoxole Triflate as a Versatile Reagent for Iodo(III)cyclization of Alkynes
作者:Bin Wu、Junliang Wu、Naohiko Yoshikai
DOI:10.1002/asia.201701530
日期:2017.12.14
Hyperactive: A benziodoxole triflate promotes iodo(III)cyclization of alkynes tethered to a variety of nucleophilic moieties, affording benziodoxole-appended (hetero)arenes such as benzofurans, benzothiophenes, isocoumarins, indoles, and polyaromatics. These unprecedented (hetero)aryl-IIII compounds are easy to purify, air- and thermally stable, and amenable to various synthetic transformations.
Catalyst-Free Synthesis of Borylated Lactones from Esters via Electrophilic Oxyboration
作者:Darius J. Faizi、Adena Issaian、Ashlee J. Davis、Suzanne A. Blum
DOI:10.1021/jacs.5b12989
日期:2016.2.24
A catalyst-free oxyboration reaction of alkynes is developed. The resulting borylated isocoumarins and 2-pyrones are isolated as boronic acids, pinacolboronate esters, or potassium organotrifluoroborate salts, providing a variety of bench-stable organoboron building blocks for downstream functionalization. This method has functional group compatibility, is scalable, and proceeds with readily available
Divergent syntheses of iodinated isobenzofuranones and isochromenones by iodolactonization of 2-alkynylbenzoic acids in ionic liquids
作者:Raffaella Mancuso、Christian C. Pomelli、Francesco Malafronte、Asif Maner、Nadia Marino、Cinzia Chiappe、Bartolo Gabriele
DOI:10.1039/c7ob00962c
日期:——
2-alkynylbenzoic acids, carried out at 100 °C in ionicliquids (ILs) as unconventional solvents and with molecular iodine as the iodine source, in the absence of external bases, was found to be strongly dependent on the nature of the IL medium. In particular, while the use of N-ethyl-N-methylmorpholinium dicyanamide (Mor1,2N(CN)2) promoted the stereoselective formation of (E)-3-(iodomethylene)isobenzofuran-1(3H)-ones
Divergent Syntheses of (<i>Z</i>)-3-Alkylideneisobenzofuran-1(3<i>H</i>)-ones and 1<i>H</i>-Isochromen-1-ones by Copper-Catalyzed Cycloisomerization of 2-Alkynylbenzoic Acids in Ionic Liquids
作者:Raffaella Mancuso、Christian S. Pomelli、Piera Chiappetta、Katia F. Gioia、Asif Maner、Nadia Marino、Lucia Veltri、Cinzia Chiappe、Bartolo Gabriele
DOI:10.1021/acs.joc.8b00923
日期:2018.6.15
The cycloisomerization of readily available 2-alkynylbenzoic acids 1 in ionic liquids (ILs) as recyclable reaction media has been studied under the catalytic action of CuCl2. With substrates bearing an aryl group on the triple bond, a mixture of (Z)-3-alkylideneisobenzofuran-1(3H)-ones (from 5-exo-dig cyclization) and 1H-isochromen-1-ones (from 6-endo-dig cyclization) was observed in 1-ethyl-3-methylimidazolium
在CuCl 2的催化作用下,已经研究了易得的2-炔基苯甲酸1在离子液体(ILs)中作为可循环反应介质的环异构化。在具有在三键上带有芳基的底物的情况下,(Z)-3-亚烷基亚异苯并呋喃-1(3 H)-ones(来自5 exo - dig环化反应)和1 H -isochromen-1-ones(来自6 -内型-挖环化)的1-乙基-3-甲基咪唑鎓乙基硫酸盐(EmimEtSO观察到4),同时将反应原来是仅朝向使用异苯并呋喃酮的形成选择性ñ乙基N-甲基吗啉二氰胺[Mor 1,2 N(CN)2 ]作为溶剂。当在EmimEtSO 4或Mor 1,2 N(CN)2中使用带有末端三键的底物时,也有选择地获得了5元产物。另一方面,在EmimEtSO 4中,三键上带有烷基或烯基的2-炔基苯甲酸选择性地导致1 H -isochromen-1- one ,而在Mor 1中观察到区域异构混合物的形成。2 N(CN)2。
Cy<sub>2</sub>NH·HX-Promoted Cyclizations of <i>o</i>-(Alk-1-ynyl)benzoates and (<i>Z</i>)-Alk-2-en-4-ynoate with Copper Halides to Synthesize Isocoumarins and α-Pyrone
作者:Jin-Heng Li、Yun Liang、Ye-Xiang Xie
DOI:10.1055/s-2006-958960
日期:2007.2
Cy 2 NH·HX was found to improve the cyclization reactions of o-(alk-1 -ynyl)benzoates and (Z)-alk-2-en-4-ynoate with CuX 2 (X = Cl, Br) to synthesize the corresponding 4-haloisocoumarins and 5-bromo-2-pyrone, respectively. In the presence of two equivalents of CuCl 2 , cyclization of methyl2-(2-phenylethynyl)benzoate was conducted smoothly to afford the corresponding desired product in 83% yield after