- New synthesis of substituted isoindolines from furans via epoxyisoindolines
-
The preparation of substituted N-arylisoindolines 3 from simple furan derivatives 1 is reported. Oxatricycloadducts 2, readily accessible by intramolecular Diels-Alder reaction are susceptible to acidic reagents yielding aromatized products 3 by a ring-op
- Mance,Borovicka,Karaman,Jakopcic
-
-
Read Online
- Practical direct synthesis of: N -aryl-substituted azacycles from N -alkyl protected arylamines using TiCl4and DBU
-
A novel transformation of N-alkyl protected arylamines and cyclic ethers into N-aryl substituted azacycles is described. Alkyl groups have been used for the protection of amines in organic syntheses. In this synthesis, N-alkyl protected arylamines were reacted with cyclic ethers in the presence of TiCl4 and DBU, crucial reagents affording five- and six-membered azacycles. In particular, utilization of the novel TiCl4/DBU-mediated reaction allows various N-alkyl protected arylamines such as N-methyl-, N-ethyl-, N-isopropyl, and N-tert-butyl arylamines to be readily converted into N-aryl substituted azacycles in high yields. This practical approach using various N-alkyl arylamines leads to the efficient preparation of azacycles.
- Kang, Soosung,Kim, Hee-Kwon,La, Minh Thanh,Tran, Van Hieu
-
p. 5008 - 5016
(2020/07/30)
-
- Synthesis of 2-Arylisoindoline Derivatives Catalyzed by Reusable 1,2,4-Triazole Iridium on Mesoporous Silica through a Cascade Borrowing Hydrogen Strategy
-
Covalent attachment of a 1,2,4-triazole iridium complex to mesoporous MCM-41 generated a heterogeneous catalyst that was found to be effective in the synthesis of 2-aryl isoindolines, quinolines, cyclic amines, and symmetrical secondary amines through a cascade borrowing hydrogen strategy. Interestingly, the supported heterogeneous iridium catalyst prepared from the 1,2,4-triazole iridium complex and mesoporous MCM-41 exhibited high catalytic activity in the preparation of 2-aryl isoindoline derivatives and symmetrical secondary amines. The catalyst system is highly recyclable for at least five times. Besides the important effect of the triazole, iridium sites grafted on siliceous supports can act as multifunctional catalytic centers and thus greatly enhance the catalytic activity of the catalysts. Furthermore, mechanistic experiments revealed that the reaction is initiated by an initial alcohol dehydrogenation and promoted by an iridium hydride intermediate. Importantly, the direct detection of a diagnostic iridium hydride signal confirmed that the synthesis of 2-aryl isoindolines occurs by a borrowing hydrogen process. This work provides an efficient example of isoindolines synthesis through a borrowing hydrogen strategy.
- Yao, Wei,Ge, Chenyang,Zhang, Yilin,Xia, Xiao-Feng,Wang, Long,Wang, Dawei
-
supporting information
p. 16099 - 16105
(2019/11/26)
-
- Metal-Free Synthesis of N-Aryl-Substituted Azacycles from Cyclic Ethers Using POCl3
-
A facile method for the synthesis of N-aryl-substituted azacycles from arylamines and cyclic ethers has been developed. In this study, arylamines were treated with cyclic ethers in the presence of POCl3 and DBU to provide five- A nd six-membered azacycles. Using this method, various azacycloalkanes, isoindolines, and tetrahydroisoquinolines were prepared in high yields. This synthetic method offers an efficient approach to the production of azacycles from cyclic ethers.
- La, Minh Thanh,Kang, Soosung,Kim, Hee-Kwon
-
p. 6689 - 6696
(2019/06/14)
-
- Isoindolinone Synthesis: Selective Dioxane-Mediated Aerobic Oxidation of Isoindolines
-
N-Alkyl and N-aryl-isoindolinones were prepared by a dioxane-mediated oxidation of isoindoline precursors. The transformation exhibits unique chemoselectivity for isoindonlines. A chiral tertiary (3°)-benzylic position was not racemized during oxidation, and methyl indoprofen was prepared by late stage oxidation. Mechanistic studies suggest a selective H atom transfer, which avoids many known oxidation (by-)products of isoindolinones.
- Thapa, Pawan,Corral, Esai,Sardar, Sinjinee,Pierce, Brad S.,Foss, Frank W.
-
p. 1025 - 1034
(2019/01/24)
-
- Visible-light induced isoindoles formation to trigger intermolecular diels-alder reactions in the presence of air
-
Visible-light induced isoindole formation triggered an intermolecular Diels-Alder reaction with dienophiles such as acetylenedicarboxylate and maleimides in the presence of air. The reaction resulted in excellent diastereoselctivity and high yields under
- Lin, Chao,Zhen, Le,Cheng, Yong,Du, Hong-Jin,Zhao, Hui,Wen, Xiaoan,Kong, Ling-Yi,Xu, Qing-Long,Sun, Hongbin
-
supporting information
p. 2684 - 2687
(2015/06/16)
-
- An efficient method for the synthesis of 2, 3-dihydro-lH-isoindoles
-
The synthesis of Af-substituted 2, 3-dihydro-lH-isoindoles from α, α'-dibromo-o-xylene and various primary amines in basic medium under ambient conditions is described. Especially the selection of 1, 4-dioxane as solvent and sodium hydroxide as suitable base to maintain the homogeneity of the medium are key steps to promote the reaction efficiently. Primary alkyl amines react faster as compared to their aromatic analogues under the conditions studied. Irrespective of the starting amine used, all the reactions proceed smoothly and provide 2, 3-dihydro-lH-isoindoles derivatives in excellent yields compared to hitherto known methods.
- Subbarayappa, Adimurthy,Patoliya, Paresh U.
-
experimental part
p. 545 - 552
(2009/12/06)
-
- Preparation of 2-substituted 1,3-bis(benzotriazol-1-yl)isoindolines by the double mannich conden-sation reaction of o-phthalaldehyde with primary amines in the presence of 1,2,3-1 h-benzotriazole
-
The preparation of isoindolines (1,3-dihydro-2H-isoindoles) possessing two reactive centers as mixed aminals is investigated. In the double Mannich condensation reaction of o-phthalaldehyde with a variety of primary amines in the presence of 1,2,3-1H-benzotriazole (Bt-H) in MeCN, Bt-substituted isoindolines are obtained in fair to good yields when anilines are used as amines.
- Takahashi, Ichiro,Tsuzuki, Mikio,Yokota, Hiroshi,Morita, Toshio,Kitajima, Hidehiko,Isa, Kimio
-
-
- CHARGE-TRANSFER COMPLEXES OF ISOINDOLINES WITH 1,4-BENZOQUINONES
-
Charge-transfer (CT) complexes of various N-arylisoindolines as donors with 1,4-benzoquinones as ?-acceptors have been studied spectrophotometrically.Effects of substituents
- Mourad, Aboul-fetouh E.,Nour-el-din, Ahmed M.,Hassan, Alaa A.,Doepp, Dietrich
-
p. 1045 - 1052
(2007/10/02)
-