19375-67-8Relevant articles and documents
BEHAVIOR OF PROPARGYL- AND ALLYLPROPARGYL-AMMONIUM SALTS IN AQUEOUS ALKALINE MEDIUM. SYNTHESIS OF 2-METHYL-2-PHENYLBENZISOINDOLINIUM AND 2-METHYL-2-PHENYLISOINDOLINIUM SALTS
Chukhadzhyan, E. O.,Manasyan, L. A.,Chukhadzhyan, El. O.,Shakhatuni, K. G.,Babayan, A. T.
, p. 58 - 62 (1995)
Methylphenylpropargyl-(3-phenylpropargyl)-ammonium bromide salts are cyclized almost quantitatively under base-catalysis conditions with the formation of 2-methyl-2-phenylbenzisoindolinium bromide.The allyl analog is subject to rearrangement-decomposit
Oxidative Desymmetrization of Isoindolines Realized by tert -Butyl Nitrite (TBN) Initiated Radical sp 3C-H Activation Relay (CHAR)
Sun, Zheng,Shao, Yu,Zhang, Shuwei,Zhang, Yuxian,Yuan, Yu,Jia, Xiaodong
, p. 1663 - 1671 (2021/02/01)
An oxidative desymmetrization of isoindolines was realized by TBN initiated radical sp 3C-H activation relay (CHAR), providing a series of ω-hydroxylactams in high yields. This reaction exhibits broad substrate scope and functional group tolerance, and even N -alkyl iso-indolines can be well tolerated. The mechanistic study shows that the C-H bond oxidation, dioxygen trapping and intramolecular 1,5-H shift might be the key steps to achieve the oxidative desymmetrization.
Solvent-driven C(sp3)-H thiocarbonylation of benzylamine derivatives under catalyst-free conditions
Zhou, Jingwei,Wang, Songping,Lu, Yaoming,Li, Lamei,Duan, Wentao,Wang, Qi,Wang, Hong,Wei, Wentao
supporting information, p. 767 - 773 (2021/02/09)
Due to the particularity of the thiocarbonyl group (C S bond), only limited C(sp3)-H thiocarbonylation methods, especially efficient and convenient methods, have been developed for the synthesis of thioamides. Inspired by the “solvent-specifici
Practical direct synthesis of: N -aryl-substituted azacycles from N -alkyl protected arylamines using TiCl4and DBU
Kang, Soosung,Kim, Hee-Kwon,La, Minh Thanh,Tran, Van Hieu
, p. 5008 - 5016 (2020/07/30)
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.
Investigation towards the reductive amination of levulinic acid by B(C6F5)3/hydrosilane system
He, Jianghua,Wang, Tianlong,Xu, Hai,Zhang, Yuetao
, (2020/08/11)
The selective transformation of the renewable biomass resources into the highly value-added platform chemicals is essentially important for sustainable chemistry. Here we report a simple and highly efficient strategy for the synthesis of N-heterocyclic co
Diethylsilane as a Powerful Reagent in Au Nanoparticle-Catalyzed Reductive Transformations
Louka, Anastasia,Kidonakis, Marios,Saridakis, Iakovos,Zantioti-Chatzouda, Elisavet-Maria,Stratakis, Manolis
, p. 3508 - 3514 (2020/06/02)
Diethylsilane (Et2SiH2), a simple and readily available dihydrosilane, that exhibits superior reactivity, as compared to monohydrosilanes, in a series of reductive transformations catalyzed by recyclable and reusable Au nanoparticles (1 mol-%) supported on TiO2. It reduces aldehydes or ketones almost instantaneously at ambient conditions. It can be used in a one pot rapid reductive amination procedure, in which premixing of aldehyde and amine is required prior to the addition of the reducing agent and the catalyst, even in a protic solvent. An unprecedented method for the synthesis of N-arylisoindolines is also shown in the reductive amination between o-phthalaldehyde and anilines. In this transformation, it is proposed that the intermediate N,2-diphenylisoindolin-1-imines are reduced stepwise to the isoindolines. Finally, Et2SiH2 readily reduces amides into amines in excellent yields and shorter reaction times relative to previously known analogous nano Au(0)-catalyzed protocols.
B(C6F5)3-Catalyzed Deoxygenative Reduction of Amides to Amines with Ammonia Borane
Pan, Yixiao,Luo, Zhenli,Han, Jiahong,Xu, Xin,Chen, Changjun,Zhao, Haoqiang,Xu, Lijin,Fan, Qinghua,Xiao, Jianliang
supporting information, p. 2301 - 2308 (2019/01/30)
The first B(C6F5)3-catalyzed deoxygenative reduction of amides into the corresponding amines with readily accessible and stable ammonia borane (AB) as a reducing agent under mild reaction conditions is reported. This metal-free protocol provides facile access to a wide range of structurally diverse amine products in good to excellent yields, and various functional groups including those that are reduction-sensitive were well tolerated. This new method is also applicable to chiral amide substrates without erosion of the enantiomeric purity. The role of BF3 ? OEt2 co-catalyst in this reaction is to activate the amide carbonyl group via the in situ formation of an amide-boron adduct. (Figure presented.).
Synthesis of 2-Arylisoindoline Derivatives Catalyzed by Reusable 1,2,4-Triazole Iridium on Mesoporous Silica through a Cascade Borrowing Hydrogen Strategy
Yao, Wei,Ge, Chenyang,Zhang, Yilin,Xia, Xiao-Feng,Wang, Long,Wang, Dawei
supporting information, p. 16099 - 16105 (2019/11/26)
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.
Metal-Free Synthesis of N-Aryl-Substituted Azacycles from Cyclic Ethers Using POCl3
La, Minh Thanh,Kang, Soosung,Kim, Hee-Kwon
, p. 6689 - 6696 (2019/06/14)
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.
Phosphoryl chloride-mediated solvent-free synthesis of N-aryl-substituted azacycles from arylamines and cyclic ethers
Tran, Van Hieu,La, Minh Thanh,Kim, Hee-Kwon
supporting information, p. 1860 - 1863 (2019/06/19)
A solvent- and metal-free protocol for preparation of N-aryl substituted azacycles from arylamines and cyclic ethers is described. In this method, the combination of POCl3 and DBU is crucial for conversion of arylamines and cyclic ethers to five- and six-membered azacycles. Without solvent, a variety of N-aryl-substituted, five-membered azacycles (pyrrolidines, 2-methylpyrrolidines, and piperidine) and six-membered azacycles (isoindolines and tetrahydroisoquinolines) are synthesized in high yields. This green method provides a sustainable and efficient approach for the preparation of azacycles from various cyclic ethers.
