Rh(<scp>iii</scp>)-catalyzed synthesis of tetracyclic isoquinolinium salts <i>via</i> C–H activation and [4+2] annulation of 1-phenyl-3,4-dihydroisoquinolines and alkynes in ethanol
作者:Xinxin Dang、Yu He、Yingtian Liu、Xuehong Chen、Jun-Long Li、Xian-Li Zhou、Hezhong Jiang、Jiahong Li
DOI:10.1039/c8ra05443f
日期:——
An efficient and convenient method to construct tetracyclic isoquinolinium salts via [Cp*RhCl2]2 catalyzed C–H activation and [4 + 2] annulationreactions in ethanol is described. This reaction is very fast and highly efficient in the green solvent ethanol. The reaction works with a broad substrate scope affording the products in good to excellent yields in a short time. Moreover, a ratio of S/C up
A convenient and general asymmetric transferhydrogenation of a wide array of 1-aryl-3,4-dihydroisoquinoline derivatives using a [RuIICl(η6-benzene)TsDPEN] complex in combination with a 5:2 HCOOH–Et3N azeotropic mixture as a hydrogen source was developed. Under mild reaction conditions, the described catalytic transformation secured a practical synthetic access to the corresponding valuable chiral
Strategies and Synthetic Methods Directed Toward the Preparation of Libraries of Substituted Isoquinolines
作者:Emelia Awuah、Alfredo Capretta
DOI:10.1021/jo100980p
日期:2010.8.20
Strategies for the production of substituted isoquinoline libraries were developed and explored. Routes involving microwave-assisted variants of the Bischler−Napieralski or Pictet−Spengler reaction allowed for cyclization of substituted β-arylethylamine derivatives. The dihydroisoquinolines and tetrahydroisoquinolines thus generated could then be oxidized to their corresponding isoquinoline analogues
Ruthenium-Catalyzed Asymmetric Transfer Hydrogenation of 1-Aryl-Substituted Dihydroisoquinolines: Access to Valuable Chiral 1-Aryl-Tetrahydroisoquinoline Scaffolds
Give me an H! Give me another H! The first general and highly enantioselective Ru‐catalyzed transferhydrogenation of a wide range of 1‐aryl‐substituted 1,2,3,4‐dihydroisoquinolines is described. This atom‐economic reaction proceeds under mild conditions, allowing rapid access to the corresponding biologically relevant 1‐aryl‐tetrahydroisoquinoline derivatives, in high yields and enantioselectivities
4-dihydroisoquinolines undergo smooth acetoxylation/alkoxylation in the presence of 5 mol % Pd(OAc)2 and a stoichiometric amount of PhI(OAc)2 by means of C–H activation to produce the corresponding acetoxy- and alkoxy-1-aryl-3,4-dihydroisoquinoline derivatives respectively in good yields with high regioselectivity. It is a first example on oxidative functionalization of arenes tethered to dihydroisoquinoline moiety