89525-51-9Relevant academic research and scientific papers
Palladium-Catalyzed α-Arylation of Silylenol Ethers in the Synthesis of Isoquinolines and Phenanthridines
Saini, Gaurav,Kumar, Pravin,Kumar, Gangam Srikanth,Mangadan, Arun Raj Kizhakkayil,Kapur, Manmohan
supporting information, p. 441 - 444 (2018/01/28)
A diverse array of isoquinolines and phenanthridines have been accessed by developing a two-step, one-pot method constituting regioselective palladium-catalyzed Kuwajima-Urabe α-arylation of silylenol ethers and acid-mediated deprotection, annulation, and aromatization. Structural diversity in the silylenol ethers leads to three different classes of isoquinolines and phenanthridines from which related natural products can be derived. The synthetic utility of this method by the quick assembly of the natural product trispheridine is also demonstrated.
Total Synthesis of (?)-Histrionicotoxin through a Stereoselective Radical Translocation–Cyclization Reaction
Sato, Manabu,Azuma, Hiroki,Daigaku, Akihiro,Sato, Sota,Takasu, Kiyosei,Okano, Kentaro,Tokuyama, Hidetoshi
supporting information, p. 1087 - 1091 (2017/01/18)
Stereoselective total syntheses of (?)-histrionicotoxin and (?)-histrionicotoxin 235A are described. The 1-azaspiro[5.5]undecane skeleton was constructed diastereoselectively by a radical translocation–cyclization reaction involving a chiral cyclic acetal; the use of tris(trimethylsilyl)silane was crucial for the high diastereoselectivity. The cyclization product was converted into (?)-histrionicotoxin 235A through a one-pot partial-reduction–allylation reaction of a derivative containing an unprotected lactam. Finally, two terminal alkenes were transformed into enynes with the 1,3-amino alcohol protected as an oxathiazolidine oxide to complete the total synthesis of (?)-histrionicotoxin.
Rapid and convergent assembly of natural benzo[c]phenanthridines by palladium/norbornene catalysis
Deyris, Pierre-Alexandre,Caneque-Cobo, Tatiana,Gomes, Filipe,Narbonne, Vanessa,Maestri, Giovanni,Malacria, Max
, p. 807 - 815 (2016/09/09)
A straightforward total synthesis of a small panel of natural benzo[c]phenanthridines is described. The selective coupling of an aryl triflate with a bromobenzylamine by means of palladium/norbornene joint catalysis and a sequential transfer hydrogenation
Synthesis of pyrrolophenanthridine alkaloids based on C(sp3)-H and C(sp2)-H functionalization reactions
Tsukano, Chihiro,Muto, Nobusuke,Enkhtaivan, Iderbat,Takemoto, Yoshiji
, p. 2628 - 2634 (2014/10/15)
Assoanine, pratosine, hippadine, and dehydroanhydrolycorine belong to the pyrrolophenanthridine family of alkaloids, which are isolated from plants of the Amaryllidaceae species. Structurally, these alkaloids are characterized by a tetracyclic skeleton that contains a biaryl moiety and an indole core, and compounds belonging to this class have received considerable interest from researchers in a number of fields because of their biological properties and the challenges associated with their synthesis. Herein, a strategy for the total synthesis of these alkaloids by using C-H activation chemistry is described. The tetracyclic skeleton was constructed in a stepwise manner by C(sp 3)-H functionalization followed by a Catellani reaction, including C(sp2)-H functionalization. A one-pot reaction involving both C(sp3)-H and C(sp2)-H functionalization was also attempted. This newly developed strategy is suitable for the facile preparation of various analogues because it uses simple starting materials and does not require protecting groups.
CuI-catalyzed coupling of gem-dibromovinylanilides and sulfonamides: An efficient method for the synthesis of 2-amidoindoles and indolo[1,2-a] quinazolines
Kiruthika, Selvarangam E.,Perumal, Paramasivan Thirumalai
supporting information, p. 484 - 487 (2014/04/03)
A Cu(I)-catalyzed, intermolecular protocol for the synthesis of 2-amidoindoles and tetrahydroindolo[1,2-a]quinazolines in shorter time and high yields is reported. The key highlight of this disclosure is the formation of 2-amidoindole and tetrahydroindolo[1,2-a]quinazoline moieties directly from gem-dibromovinylanilides and sulfonamides in a one-pot fashion through the in situ formation of ynamides followed by a base-promoted intramolecular hydroamidation.
Tricyclic isoindolines by Heck cyclization
Satyanarayana, Gedu,Maier, Martin E.
, p. 1745 - 1749 (2012/03/10)
A series of 4-formyl esters 8a-d was prepared by Michael addition of an enamine with ethyl acrylate. A subsequent condensation with 2-bromobenzylamines 3 gave rise to cyclic enamides 9aa-dd. In a Heck cyclization reaction tricyclic isoindoles 10aa-dd were formed in good yields.
PALLADIUM ASSISTED ORGANIC REACTIONS. VII. THE PREPARATION OF CYCLOPALLADATED PRIMARY AND SECONDARY BENZYLAMINES
Clark, P. W.,Dyke, S. F.
, p. 389 - 396 (2007/10/02)
A new method is described for the preparation of cyclopalladated benzylamines, involving the reaction of the ortho-bromobenzylamines with bis(dibenzylideneacetone)palladium(0).By using this method cyclopalladated complexes of simple primary and secondary benzylamines have been obtained for the first time.These complexes have been fully characterised as either the monomeric bromo(benzylamine-6-C,N)triphenylphosphinepalladium(II) derivatives or as the corresponding acetyl-acetonates. 1H and 13C NMR spectral data have been obtained and, in most cases, full assignments have been made.
