Palladium-Catalyzed Asymmetric Domino Heck/Carbocyclization/Suzuki Reaction: A Dearomatization of Nonactivated Naphthalenes

Abstract

Herein, we report a novel palladium (Pd)-catalyzed asymmetric domino Heck/carbocyclization/Suzuki reaction of N-(2-bromoaryl)-2-naphthylacrylamides. The reaction involves a novel and enantioselective dearomative 1,2-insertion of the naphthalene group, thus providing a unique dearomatization strategy of nonactivated naphthalenes. A new phosphoramidite ligand L12, which displayed excellent reactivity and enantioselectivity in the reaction, has been developed. The reaction employs readily available starting materials, and provides straightforward access to a diverse array of spirooxindoles bearing three stereogenic centers in high yields under mild conditions.

Palladium-Catalyzed [3 + 2] Annulation of Alkynes with Concomitant Aromatic Ring Expansion: A Concise Approach to (Pseudo)azulenes

“…The reaction is proposed to involve the formal trans-palladium-boration of the internal alkyne, cis-addition of an alkyne, dearomative spiroannulation, and ring expansion process, in which iodide is proposed to act as a pivotal ligand to trigger the reaction and drive the cis–trans isomerization of boroalkenyl palladium species. This reaction is impressive considering that the following challenges encountered can be overcome: (a) while much success has been achieved on transition-metal-catalyzed cis-selective borylative 1,2-difunctionalization of alkynes, relatively fewer reports have been disclosed on such reactions involving a trans-selective mode; (b) the dearomatization process is thermodynamically disfavored owing to the high aromatic stabilization energy of planar arenes; , and (c) a number of possible side reactions have to be avoided such as the protonation of highly reactive organopalladium intermediates, diborylative addition, and protodeborylation and cyclopolymerization of alkynes. , In the present paper, we report our synthesis together with study of the reaction mechanism.…”

Spirocyclizative Remote Arylcarboxylation of Nonactivated Arenes with CO 2 via Visible-Light-Induced Reductive Dearomatization

“…In contrast, only limited important advances have been made in the dearomatization of electronically unbiased aromatics such as naphthalene and benzene derivatives that possess high resonance stabilization energy. 6,[25][26][27][28][29][30][31][32][33][34][35] Of particular note, the You's group and the Hong and Jia's group simultaneously reported two types of elegant highly diastereoselective 1,4-difunctionalization reactions of 1-naphthamides via palladium-catalyzed dearomatization at slightly elevated temperature. 25,26 Therefore, the dearomatization of non-activated arenes remains challenging, and the development of a mild and complementary protocol for dearomatization of non-activated arenes is highly desirable.…”

Asymmetric dearomative cyclopropanation of naphthalenes to construct polycyclic compounds

“…To date, sporadic dearomatization reactions of naphthalenes with high enantioselectivity have been developed. 6–8 Recently, an enantioselective dearomative difunctionalization of naphthalenes was achieved by Sarlah's group, which involved visible-light-mediated [4 + 2] cycloaddition of naphthalenes with an arenophile and subsequent asymmetric ring-opening of the resulting cycloadducts. 6 In 2022, Jia, Zhang and You developed a Pd-catalyzed intramolecular dearomative Mizoroki–Heck reaction of naphthalenes to construct spirooxindole and spiroisoindolin-1-one with high enantioselectivity (Scheme 1b).…”