The C–H Activation/Bidirecting Group Strategy for Selective Direct Synthesis of Diverse 1,1′-Biisoquinolines

Abstract

Multidentate ligands are highly important but difficult to access. Herein we disclose an atom- and step-economic synthesis of highly substituted 1,1′-biisoquinolines by a C–H activation/bididirecting group strategy. Through rational design of a bididirecting group to “N–OH + N–OAc”, selective unsymmetrical diannulation with two different alkynes in a one-pot reaction has been achieved for the first time to access unsymmetrical biisoquinolines. Moreover, the resultant biisoquinolines show tunable photoluminescence and serve as aggregation-induced emission (AIE) systems.

Experimental and computational studies on rhodium-catalyzed C4(5)aryl–H activation/annulation of imidazoles with alkynes: facile synthesis of six types of N-heterocycles

“…24 Gratifyingly, by treatment of 1-E with 2 molecules of alkyne, 1,1′-bisisoquinolines 8a and 8b could be efficiently obtained in fair yields through an unprecedented ring-opening, decarbonylative double C-H annulation, which serves as a complementary method to our previous work. 25 These results revealed that both the C4 and C5 aryls can be activated when the imidazole ring is destroyed.…”

Late‐Stage Functionalization for the Divergent Synthesis of Podophyllotoxin Derivatives by Rhodium Catalysis

“…A plausible mechanism is proposed on the basis of preliminary mechanistic experiments and literature precedents. [18] As shown in Scheme 5, the five-membered rhodacycle A intermediate was formed by coordination, and undergoes CÀ H bond cleavage at the C5 position. For ketone substrate, the rhodacycle A could convert into intermediate B through the transmetalation with 2 a, then the reductive elimination of intermediate B gives rise to the desired product 3 aa and Rh I species.…”

Rh(III)-Catalyzed One-Pot Three-Component Diannulation of Benzils, Ammonium Acetate, and Alkynes to Build 1,1′-Biisoquinolines

“…Unless otherwise noted, all reagents and solvents were obtained from commercial suppliers such as Aladdin, Beijing Innochem Chemical Engineering Reagent (China) Co., Ltd., Energy Chemical, etc., and used without further purification. [(Cp*RhCl 2 ) 2 ] alkynes and [D 10 ]- 1a were prepared according to the literature procedures. Unless otherwise noted, all reaction mixtures were heated with aluminum heating blocks and detected by TLC (thin layer chromatography) with silica gel-coated plates.…”

“…Despite the fact that they are valuable examples of BIQ synthesis, they cannot be shown to synthesize 1,1′-BIQs, and extra steps are needed to install the DGs. Recently, our group reported a C–H activation/bidirecting group strategy for producing 1,1′-BIQs from Z,Z -type dioximes and alkynes (Scheme b); however, Z,Z -type dioximes need extra preparation, and other undesired Z,E - and E,E -type isomers may be generated. Herein, we further pave the way for the synthesis of 1,1′-BIQs through a three-component reaction of commercially available raw materials, benzils, ammonium acetate, and alkynes (Scheme c).…”