Palladium-catalyzed δ-selective reductive Heck reaction of alkenyl carbonyl compounds with aryl iodides and bromides

Abstract

<p>A palladium-catalyzed δ-selective reductive Heck reaction of 4-pentenoic acid derivatives bearing an 8-aminoquinoline directing group with aryl iodides and bromides has been developed. The reactions were carried out by using...</p>

Controllable access to trifluoromethyl-containing indoles and indolines: palladium-catalyzed regioselective functionalization of unactivated alkenes with trifluoroacetimidoyl chlorides

“…Based on the mechanistic investigation and the precedent literature, 2 g ,12,15–17 the plausible reaction mechanisms of two different difunctionalizations of unactivated alkenes were proposed as depicted in Scheme 3. For the 1,1-difunctionalization reaction, the oxidative addition of C–I bond of trifluoroacetimidoyl chloride 1a to Pd(0) generated imidoyl Pd( ii ) intermediate A , which coordinated with the directing group in the alkene 2a to form complex B .…”

Metal‐Catalysed Synthesis of Benzofused Five‐Membered N/O/S‐Heterocycles, a Progressive Area in Synthetic Organic Chemistry

“…In fact, such a method has been acknowledged as one of the most alluring methods to access alkylated aromatics with adjustable regioselectivity because it can bestow the new double CÀ C activation mode. [91] Motivated by the developed protocols, in 2021, Jiang and co-workers revealed a regioselective hydroarylation reaction of alkenes [92] as a unique method for the synthesis of various C3-alkylated benzofurans for the first time. Here, αalkynyl arylols 60 treated with the 8-aminoquinoline directing group protected unactivated alkenes 74 under palladium acetate to form substituted benzofuran 75 (Scheme 21).…”

“…Notably, the AQ directing group‘s presence suppresses a rival β‐H elimination process in order to regulate the regioselectivity of the addition. In fact, such a method has been acknowledged as one of the most alluring methods to access alkylated aromatics with adjustable regioselectivity because it can bestow the new double C−C activation mode [91] . Motivated by the developed protocols, in 2021, Jiang and co‐workers revealed a regioselective hydroarylation reaction of alkenes [92] as a unique method for the synthesis of various C3‐alkylated benzofurans for the first time.…”

Palladium-Catalyzed Reductive Heck Hydroarylation of Unactivated Alkenes Using Hydrosilane at Room Temperature

“…The first palladium-catalyzed reductive Heck hydroarylation was reported by Cacchi in 1983 using α,β-unsaturated ketones and aryl iodides. Since then, inter- and intramolecular reductive Heck hydroarylation reactions have been developed using various substrates that have been classified into four types: activated (conjugated), − unactivated (nonconjugated), − strained (lack β-hydrogens), and tethered alkenes , (aryl halide groups in the same molecules). However, unactivated alkenes have not been widely used in this reaction, except for intramolecular coupling, because substrates with no electronic differences between two olefinic sites cannot undergo regioselective hydroarylation.…”