26385-33-1Relevant academic research and scientific papers
Cobalt salt-catalyzed carbocyclization reactions of α-bromo-N-phenylacetamide derivatives
Cheng, Yi-Chen,Chen, Ying-Yu,Chuang, Che-Ping
, p. 2020 - 2032 (2017)
An efficient and low-cost method for the synthesis of 4-substituted quinolin-2-(1H)-ones has been developed. In the presence of TBHP, the cobalt(ii)-catalyzed carbocyclization reactions of arylethenyl substituted α-bromo-N-phenylacetamides, involving sequential 6-exo-trig radical cyclization, t-butylperoxy radical cross-coupling reaction and the base-promoted ionic Kornblum-DeLaMare reaction, produced 4-benzoylquinolin-2-(1H)-ones. A variety of useful functional groups such as methoxy, fluoro, chloro, bromo, methoxycarbonyl, and cyano groups, are compatible with the reaction conditions. This strategy was further applied to arylethynyl substituted α-bromo-N-phenylacetamides, and 4-benzylquinolin-2-(1H)-ones were formed effectively.
Metal-Free and syn-Selective Hydrohalogenation of Alkynes through a Pseudo-Intramolecular Process
Asahara, Haruyasu,Mukaijo, Yusuke,Muragishi, Kengo,Iwai, Kento,Ito, Akitaka,Nishiwaki, Nagatoshi
, p. 5747 - 5755 (2021/10/20)
A new metal-free hydrohalogenation method for alkynes has been developed, which proceeds through a pseudo-intramolecular process. In this reaction, ethynylaniline serves as a substrate to quantitatively form an anilinium salt upon treatment with hydrochloric acid. The spatial proximity facilitates the efficient electrophilic addition of HCl to the ethynyl group in syn-mode, affording the corresponding chloroalkene without overaddition. This protocol was applied to HBr and HI, and the corresponding bromo- and iodoalkenes were obtained, respectively. The obtained chloroalkene was converted to tri-substituted alkenes possessing different aryl/alkynyl groups through Pd-catalyzed cross-coupling reactions.
Monohydride-Dichloro Rhodium(III) Complexes with Chiral Diphosphine Ligands as Catalysts for Asymmetric Hydrogenation of Olefinic Substrates
Higashida, Kosuke,Brüning, Fabian,Tsujimoto, Nagataka,Higashihara, Kenya,Nagae, Haruki,Togni, Antonio,Mashima, Kazushi
supporting information, p. 8749 - 8759 (2020/07/04)
We report full details of the synthesis and characterization of monohydride-dichloro rhodium(III) complexes bearing chiral diphosphine ligands, such as (S)-BINAP, (S)-DM-SEGPHOS, and (S)-DTBM-SEGPHOS, producing cationic triply chloride bridged dinuclear rhodium(III) complexes (1 a: (S)-BINAP; 1 b: (S)-DM-SEGPHOS) and a neutral mononuclear monohydride-dichloro rhodium(III) complex (1 c: (S)-DTBM-SEGPHOS) in high yield and high purity. Their solid state structure and solution behavior were determined by crystallographic studies as well as full spectral data, including DOSY NMR spectroscopy. Among these three complexes, 1 c has a rigid pocket surrounded by two chloride atoms bound to the rhodium atom together with one tBu group of (S)-DTBM-SEGPHOS for fitting to simple olefins without any coordinating functional groups. Complex 1 c exhibited superior catalytic activity and enantioselectivity for asymmetric hydrogenation of exo-olefins and olefinic substrates. The catalytic activity of 1 c was compared with that of well-demonstrated dihydride species derived in situ from rhodium(I) precursors such as [Rh(cod)Cl]2 and [Rh(cod)2]+[BF4]? upon mixing with (S)-DTBM-SEGPHOS under dihydrogen.
Synthesis of 2,3-disubstituted indoles from alkynylanilines and 2-chlorophenols using palladium–dihydroxyterphenylphosphine catalyst
Yamaguchi, Miyuki,Ogihara, Kota,Konishi, Hideyuki,Manabe, Kei
supporting information, (2020/04/15)
2,3-Disubstituted indoles bearing 2-hydroxyphenyl moieties at their C3 positions were synthesized from readily available 2-chlorophenols and alkynylanilines via aminopalladation/reductive elimination using Pd–dihydroxyterphenylphosphine catalyst. The catalyst accelerates the introduction of the 2-hydroxyphenyl group at the C3 position of the indole.
PtCl4-catalyzed cyclization of N-acetyl-2-alkynylanilines: A mild and efficient synthesis of N-acetyl-2-substituted indoles
Chaisan, Nattawadee,Kaewsri, Wilailak,Thongsornkleeb, Charnsak,Tummatorn, Jumreang,Ruchirawat, Somsak
, p. 675 - 680 (2018/01/18)
An efficient synthesis of N-acetyl-2-substituted indole derivatives via direct intramolecular hydroamination of N-acetyl-2-alkynylaniline derivatives was developed. The reaction could be applied to a wide range of substrates employing only 1–2 mol% of PtCl4 as the catalyst to furnish the desired indole products in moderate to excellent yields. The current protocol is efficient, reliable and scalable, and could serve as an important tool for convenient and rapid access to this important class of N-heterocyclic skeleton from readily available substrates.
An efficient synthesis of indoles via a CuMgAl-LDH-catalyzed cyclization of 2-alkynylsulfonanilides
Zhang, Sheng-Yan,Sun, Shan-Gang,Guo, Yu-Shuang,Lu, Xiao-Fan,Guo, Dian-Shun
, p. 3719 - 3723 (2018/09/14)
A highly efficient method for the synthesis of indoles has been successfully developed via a CuMgAl-LDH-catalyzed intramolecular annulation reaction of 2-alkynylsulfonanilides. This CuMgAl-LDH catalyst features facile preparation, recovery, and reuse at l
Synthesis of Benzofurans and Indoles from Terminal Alkynes and Iodoaromatics Catalyzed by Recyclable Palladium Nanoparticles Immobilized on Siliceous Mesocellular Foam
Bruneau, Alexandre,Gustafson, Karl P. J.,Yuan, Ning,Tai, Cheuk-Wai,Persson, Ingmar,Zou, Xiaodong,B?ckvall, Jan-E.
, p. 12886 - 12891 (2017/09/25)
Herein, we report on the utilization of a heterogeneous catalyst, consisting of Pd nanoparticles supported on a siliceous mesocellular foam (Pd0-AmP-MCF), for the synthesis of heterocycles. Reaction of o-iodophenols and protected o-iodoanilines with acetylenes in the presence of a Pd nanocatalyst produced 2-substituted benzofurans and indoles, respectively. In general, the catalytic protocol afforded the desired products in good to excellent yields under mild reaction conditions without the addition of ligands. Moreover, the structure of the reported Pd nanocatalyst was further elucidated with extended X-ray absorption fine-structure spectroscopy, and it was proven that the catalyst could be recycled multiple times without significant loss of activity.
One-Pot Synthesis of Substituted Benzo[b]furans and Indoles from Dichlorophenols/Dichloroanilines Using a Palladium-Dihydroxyterphenylphosphine Catalyst
Yamaguchi, Miyuki,Akiyama, Tomoyo,Sasou, Hirohisa,Katsumata, Haruka,Manabe, Kei
, p. 5450 - 5463 (2016/07/14)
Disubstituted benzo[b]furans were synthesized by ortho-selective Sonogashira coupling of dichlorophenols and terminal alkynes, followed by cyclization and Suzuki-Miyaura coupling in one pot, using a palladium-dihydroxyterphenylphosphine (Cy-DHTP) catalyst. The use of substoichiometric amounts of tetrabutylammonium chloride was effective in accelerating the Suzuki-Miyaura coupling. This protocol was also successfully applied to the one-pot synthesis of disubstituted indoles from dichloroaniline derivatives.
A concise approach for the synthesis of 3-iodoindoles and 3-iodobenzo[b]furans via Ph3P-catalyzed iodocyclization
Li, Yin-Long,Li, Jian,Yu, Sheng-Nan,Wang, Ji-Bo,Yu, Yan-Min,Deng, Jun
supporting information, p. 8271 - 8277 (2015/10/05)
A variety of 3-iodoindole and 3-iodobenzo[b]furan derivatives were conveniently prepared from the corresponding 2-alkynylanilines and 2-alkynylphenols through Ph3P-catalyzed iodocyclization in the presence of N-iodosuccinimide (NIS). This proto
One-pot synthesis of 2,4-disubstituted indoles from N-tosyl-2,3- dichloroaniline using palladium-dihydroxyterphenylphosphine catalyst
Yamaguchi, Miyuki,Manabe, Kei
supporting information, p. 2386 - 2389 (2014/05/20)
4-Chloroindoles were synthesized from readily available 2,3-dichloroaniline derivatives and terminal alkynes. The catalyst composed of palladium and dicyclohexyl(dihydroxyterphenyl)phosphine (Cy-DHTP) enabled ortho-selective Sonogashira coupling, and subsequent cyclization afforded 4-chloroindoles in high yields. This transformation was successfully applied to the one-pot synthesis of 2,4-disubstituted indoles via Suzuki-Miyaura coupling after indole formation.
