1135318-19-2Relevant academic research and scientific papers
Silver/Rhodium Relay Catalysis Enables C?H Functionalization of In Situ Generated Isoquinolines with Sulfoxonium Ylides: Construction of Hexahydrodibenzo[a,g]quinolizine Scaffolds
Li, Quanzhe,Liu, Ruixing,Wei, Yin,Shi, Min
supporting information, p. 2664 - 2669 (2021/04/05)
Employing silver/rhodium relay catalysis strategy, an intramolecular electrophilic cyclization and C?H activation followed by cascade hydrogenation and reductive amination has been developed. The acylmethylated isoquinoline derivatives could be afforded with broad substrate scope in 23–88% yields, which could be further transformed to the core skeleton of hexahydrodibenzo[a,g]quinolizine as drug-candidates. Moreover, this reaction was achieved in a gram-scale. A reasonable reaction mechanism has been proposed based on a series of control and KIE experiments. (Figure presented.).
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
, 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.
Study on the iodine-catalyzed reaction of 3-aminopyrazine-2-carbohydrazide and 2-(arylethynyl)benzaldehydes
Pan, Wan-Chen,Liu, Jian-Quan,Wang, Xiang-Shan
, p. 1468 - 1475 (2018/02/19)
At 60 °C in DMSO, the iodine-catalyzed reaction of 3-aminopyrazine-2-carbohydrazide and 2-(arylethynyl)benzaldehydes led hydrazones. Increasing the reaction temperature to 100 °C, the amino and amido still indicated inactive, only the imine took part in the addition of acetylene bond to give 2-arylisoquinolines in high yields with the cleavage of N-N bond unexpectedly under metal-free conditions.
Palladium-catalyzed enolate arylation as a key C-C bond-forming reaction for the synthesis of isoquinolines
Pilgrim, Ben S.,Gatland, Alice E.,Esteves, Carlos H. A.,McTernan, Charlie T.,Jones, Geraint R.,Tatton, Matthew R.,Procopiou, Panayiotis A.,Donohoe, Timothy J.
, p. 1065 - 1090 (2016/01/15)
The palladium-catalyzed coupling of an enolate with an ortho-functionalized aryl halide (an α-arylation) furnishes a protected 1,5-dicarbonyl moiety that can be cyclized to an isoquinoline with a source of ammonia. This fully regioselective synthetic route tolerates a wide range of substituents, including those that give rise to the traditionally difficult to access electron-deficient isoquinoline skeletons. These two synthetic operations can be combined to give a three-component, one-pot isoquinoline synthesis. Alternatively, cyclization of the intermediates with hydroxylamine hydrochloride engenders direct access to isoquinoline N-oxides; and cyclization with methylamine, gives isoquinolinium salts. Significant diversity is available in the substituents at the C4 position in four-component, one-pot couplings, by either trapping the in situ intermediate after α-arylation with carbon or heteroatom-based electrophiles, or by performing an α,α-heterodiarylation to install aryl groups at this position. The α-arylation of nitrile and ester enolates gives access to 3-amino and 3-hydroxyisoquinolines and the α-arylation of tert-butyl cyanoacetate followed by electrophile trapping, decarboxylation and cyclization, C4-functionalized 3-aminoisoquinolines. An oxime directing group can be used to direct a C-H functionalization/bromination, which allows monofunctionalized rather than difunctionalized aryl precursors to be brought through this synthetic route.
A room-temperature protocol to access isoquinolines through Ag(i) catalysed annulation of o-(1-alkynyl)arylaldehydes and ketones with NH4OAc: Elaboration to berberine and palmatine
Reddy, Virsinha,Jadhav, Abhijeet S.,Vijaya Anand, Ramasamy
, p. 3732 - 3741 (2015/03/30)
An efficient and mild protocol for the direct construction of aryl- and alkyl-substituted isoquinolines has been realized through silver nitrate catalyzed aromatic annulation of o-(1-alkynyl)arylaldehydes and ketones with ammonium acetate. The salient feature of this methodology is that this annulation could be effected at room temperature leading to a wide range of isoquinoline derivatives in good to excellent yields. Additionally, this approach has been employed to the synthesis of biologically important isoquinoline alkaloids such as berberine and palmatine.
Facile synthesis of 3-substituted isoquinolines derivatives via microwave-assisted tandem three-component coupling cyclization
Lin, Long,Wu, Qiongyou,Huang, Shaowei,Yang, Guangfu
experimental part, p. 1075 - 1082 (2012/08/07)
A novel three-component reaction of o-bromobenzaldehyde, terminal alkynes and tert-butyl amine has been established, which proceeded smoothly to give 3-substituted isoquinolines in good yields in the presence of palladium/copper catalysts under microwave irradiation.
AgOTf and TfOH co-catalyzed isoquinoline synthesis via redox reactions of O-alkyl oximes
Hwang, Soojin,Lee, Youngun,Lee, Phil Ho,Shin, Seunghoon
scheme or table, p. 2305 - 2308 (2009/09/06)
Under AgOTf and Br?nsted acid co-catalysis, O-alkyl o-alkynylbenzaldoxime derivatives undergo a cyclization-induced N-O cleavage to produce isoquinolines with the simultaneous oxidation of O-alkyl group. This redox-based method provides a general access t
