2220-04-4Relevant academic research and scientific papers
Metal-Free Activation of C(sp3)–H Bond, and a Practical and Rapid Synthesis of Privileged 1-Substituted 1,2,3,4-Tetrahydroisoquinolines
Choudhury, Santosh Kumar,Rout, Pragati,Parida, Bibhuti Bhusan,Florent, Jean-Claude,Johannes, Ludger,Phaomei, Ganngam,Bertounesque, Emmanuel,Rout, Laxmidhar
, p. 5275 - 5292 (2017)
The reaction of cotarnine and acyl/aryl ketones in “green” solvents provides an efficient approach to an array of privileged 1,2,3,4-tetrahydroisoquinolines in excellent yields by metal-free activation of C(sp3)–H bonds. This one-pot procedure takes place under base-free conditions at room temperature, and tolerates a wide range of functionalities. The reaction is highly chemoselective, can be performed on a multi-gram scale, and pure products are isolated by simple filtration without workup. Interestingly, the complementary two-step procedure from cotarnine halide salts gives the Mannich products in good yields. The scope was elaborated to 9-bromocotarnine salts to access a range of 9-bromonoscapine-derived analogues. The methodology has been developed considering the structural similarity of cotarnine derivatives to noscapinoids, which represent an emerging class of microtubule-modulating anticancer agents.
