1859-71-8Relevant academic research and scientific papers
Synthesis of Azepino[1,2-a]indole-10-amines via [6+1] Annulation of Ynenitriles with Reformatsky Reagent
Iioka, Ryoya,Yorozu, Kohei,Sakai, Yoko,Kawai, Rika,Hatae, Noriyuki,Takashima, Katsuki,Tanabe, Genzoh,Wasada, Hiroaki,Yoshimatsu, Mitsuhiro
supporting information, p. 1553 - 1558 (2021/02/26)
Lewis acid-catalyzed [6+1] annulation reactions of 2-cyano-1-propargyl- and 2-alkynyl-1-cyanomethyl-indoles with Reformatsky reagent are described. 8-Aryl, 8-alkyl-, 8-hetaryl-, 9-aryl, and 9-alkyl-azepino[1,2-a]indole amines were obtained through a 7-endo-mode cyclization of the β-aminoacrylate intermediates. The antiproliferative activity of the azepino[1,2-a]indoles analogs against the HCT-116 cells were also examined.
Ynamide Smiles Rearrangement Triggered by Visible-Light-Mediated Regioselective Ketyl-Ynamide Coupling: Rapid Access to Functionalized Indoles and Isoquinolines
Chen, Yang-Bo,Sun, Zhou,Wang, Ze-Shu,Ye, Long-Wu,Zhang, Hao-Wen,Zhu, Chunyin
supporting information, p. 3636 - 3644 (2020/03/06)
In the past decades, significant advances have been made on radical Smiles rearrangement. However, the eventually formed radical intermediates in these reactions are limited to the amidyl radical, except for the few examples initiated by a N-centered radical. Here, a novel and practical radical Smiles rearrangement triggered by photoredox-catalyzed regioselective ketyl-ynamide coupling is reported, which represents the first radical Smiles rearrangement of ynamides. This method enables facile access to a variety of valuable 2-benzhydrylindoles with broad substrate scope in generally good yields under mild reaction conditions. In addition, this chemistry can also be extended to the divergent synthesis of versatile 3-benzhydrylisoquinolines through a similar ketyl-ynamide coupling and radical Smiles rearrangement, followed by dehydrogenative oxidation. Moreover, such an ynamide Smiles rearrangement initiated by intermolecular photoredox catalysis via addition of external radical sources is also achieved. By control experiments, the reaction was shown to proceed via key ketyl radical and α-imino carbon radical intermediates.
Synthesis of Spirobicyclic Pyrazoles by Intramolecular Dipolar Cycloadditions/[1s, 5s] Sigmatropic Rearrangements
Dimirjian, Christine A.,Casti?eira Reis, Marta,Balmond, Edward I.,Turman, Nolan C.,Rodriguez, Elys P.,Di Maso, Michael J.,Fettinger, James C.,Tantillo, Dean J.,Shaw, Jared T.
supporting information, p. 7209 - 7212 (2019/10/02)
The formation of fused pyrazoles via intramolecular 1,3-dipolar cycloadditions of diazo intermediates with pendant alkynes is described. A subsequent thermal [1s, 5s] sigmatropic shift of these pyrazole systems resulted in a ring contraction, forming spirocyclic pyrazoles. The limitations of this rearrangement were explored by changing the substituents on the nonmigrating aromatic ring and by using substrates lacking an aromatic linkage to the propargyl group.
Manganese-Catalyzed ortho-C-H Amidation of Weakly Coordinating Aromatic Ketones
Kong, Xianqiang,Xu, Bo
supporting information, p. 4495 - 4498 (2018/08/07)
An efficient manganese-catalyzed ortho-C-H amidation of weakly coordinating aromatic ketones using the readily available sulfonyl azide as the amination reagent is developed. The key step is the ketone directed aromatic metalation using the in situ generated reactive Mn intermediate, MnMe(CO)5. This method offers excellent chemical yields, high regioselectivities, and good functional group tolerance.
Diastereoselective synthesis of 2,4-substituted tetrahydroquinolines via hf(otf)4-catalyzed substitution/cyclization of 2-aminobenzyl alcohols with styrenes
Noji, Masahiro,Kadowaki, Hiroto,Kubota, Yuuki,Yoshida, Tomomi,Saito, Noriko,Yamaguchi, Subaru,Ohata, Ren,Ishii, Keitaro,Takanami, Toshikatsu
, p. 1041 - 1073 (2017/07/27)
An efficient and convenient stereoselective synthetic approach to 2,4-substituted 1,2,3,4-tetrahydroquinoline has been developed. This catalytic procedure involves a sequential reaction of 2-aminobenzyl alcohol with styrenes in the presence of Hf(OTf)4 ca
Rhodium-Catalyzed Directing-Group-Assisted Aldehydic C–H Arylations with Aryl Halides
Rao, Maddali L. N.,Ramakrishna, Boddu S.
, p. 5080 - 5093 (2017/09/20)
A rhodium-catalyzed general protocol for the directing-group-assisted arylation of aromatic aldehydic C–H bonds was developed. This method involves either hydroxy- or amino-group-directed aldehyde C–H arylation with various aryl halides. A broad synthetic scope for the preparation of 2-hydroxybenzophenones was established with electronically variant salicylaldehydes and aryl halides with chemo- and regioselective possibilities. The developed protocol was also applied in the synthesis of medicinally important 3-salicyloylpyridines in high yields.
Iridium- and rhodium-catalyzed C-H activation and formyl arylation of benzaldehydes under chelation-assistance
Yang, Xifa,Wang, He,Zhou, Xukai,Li, Xingwei
supporting information, p. 5233 - 5237 (2016/07/06)
Mild and efficient synthesis of benzophenones via Ir(iii)- and Rh(iii)-catalyzed, directing group-assisted formyl C-H arylation of benzaldehydes has been achieved using diaryliodonium salts, in which Rh(iii) and Ir(iii) catalysts exhibited a complementary
Synthesis of polysubstituted cyclopenta[b]indoles via relay gold(i)/Bronsted acid catalysis
Dhiman, Seema,Ramasastry
, p. 557 - 560 (2015/01/09)
An efficient relay catalytic process involving Au(i)/Bronsted acid to access various polysubstituted cyclopentannulated indoles from easily accessible 1-(2-aminophenyl)prop-2-ynols and readily available 1,3-dicarbonyls has been developed. In an unprecedented event, the intermediate 2-indolylmethyl cations undergo the cation-Ene reaction with various 1,3-dicarbonyls followed by an intramolecular Friedel-Crafts-type reaction generating functionalized cyclopenta[b]indoles. This journal is
Enantioselective intramolecular C-H insertion reactions of donor-donor metal carbenoids
Soldi, Cristian,Lamb, Kellan N.,Squitieri, Richard A.,Gonzlez-Lpez, Marcos,Di Maso, Michael J.,Shaw, Jared T.
supporting information, p. 15142 - 15145 (2015/02/19)
The first asymmetric insertion reactions of donor-donor carbenoids, i.e., those with no pendant electron-withdrawing groups, are reported. This process enables the synthesis of densely substituted benzodihydrofurans with high levels of enantio- and diaste
1-(2′-Anilinyl)prop-2-yn-1-ol rearrangement for oxindole synthesis
Kothandaraman, Prasath,Koh, Bing Qin,Limpanuparb, Taweetham,Hirao, Hajime,Chan, Philip Wai Hong
supporting information, p. 1978 - 1985 (2013/03/14)
A synthetic method that relies on NIS (N-iodosuccinimide)-mediated cycloisomerization reactions of 1-(2′-anilinyl)prop-2-yn-1-ols to gem-3-(diiodomethyl)indolin-2-ones and 2-(iodomethylene)indolin-3-ones has been developed. The reactions were shown to be chemoselective, with secondary and tertiary alcoholic substrates exclusively giving the 3- and 2-oxindole products, respectively. In the case of the latter, the transformation features an unprecedented double 1,2-OH and 1,2-alkyl migration relay. Density functional theory (DFT) calculations based on proposed iodoaminocyclization species provide insight into this unique divergence in product selectivity. Copyright
