Expeditious Synthesis of Tetrasubstituted Helical Alkenes by a Cascade of Palladium‐Catalyzed CH Activations

Abstract

Nach einem modularen Ansatz wurden tetrasubstituierte helicale Alkene hergestellt. Dabei ermöglicht eine intermolekulare, Pd‐katalysierte und Norbornen‐vermittelte Dominoreaktion die Bildung dreier C‐C‐Bindungen in einem einzigen Arbeitsschritt über eine Sequenz aus C‐H‐Aktivierung, Carbopalladierung und erneuter C‐H‐Aktivierung.

Intermolecular Domino Reaction of Two Aryl Iodides Involving Two CH Functionalizations

“…Metals, including palladium, rhodium, and iridium, have been used to access a variety of ortho-or meta-directed C À H activations. [3] For over a decade, our group [4] has used variants of the palladium-catalyzed Catellani reaction [5] to direct CÀH functionalization by generating the directing group in situ and catalytically. This task has been accomplished by using norbornene as the shuttle to direct the desired C À H palladation.…”

“…a) Intramolecular arylation through[1,4]-Pd shift and final CÀH activation by Larock (2004). b) C(sp 2 ) or C(sp 3 ) functionalization of s-alkyl/Pd II intermediate E by Jia (2010).…”

Efficient Synthesis of Helical Tetrasubstituted Alkenes as Potential Molecular Switches: A Two‐Component Palladium‐Catalyzed Triple Domino Process

“…[4] Thus, the design of novel domino reactions involving palladium-catalyzed transformations of unfunctionalized aromatic scaffolds is a promising approach. [5,14] Herein, we describe a novel two-component Pd-catalyzed triple domino process, which includes a direct C À H functionalization as the last step, for the synthesis of helical tetrasubstituted alkenes. Helical alkenes, first described by Feringa and Wynberg, [6] represent a new class of compounds that has attracted great interest in the past decade owing to their high potential to act as analogues of mechanical machines and motors, as well as electronic devices, on the molecular level.…”

1,3-Dien-5-ynes: Versatile Building Blocks for the Synthesis of Carbo- and Heterocycles

“…1). 186 The obtained compounds could have interesting potential applications in the field of light-driven molecular devices.…”