Transition metal-catalyzed cross-coupling reactions of functionalized organometallic reagents
type: CreativeWork
description: In summary, reaction conditions have been found for a versatile nickel-catalyzed crosscoupling reaction in the presence of an electron deficient styrene promoter, allowing for the first time: · effective coupling of readily available functionalized alkylzinc halides and benzylic zinc bromides with functionalized alkyl iodides in the presence of TBAI · the application of alkyl bromides in a Csp3-Csp3 cross-coupling reaction. Furthermore, · the presence of sensitive functional groups such as an amino function with an unprotected NH group is tolerated · coupling of diastereomerically enriched zinc reagents proceed with high retention of configuration at the zincated carbon · scaling up can be achieved without significant loss of chemical yield. In summary, an effective and high yielding protection-deprotection protocol has been developed for the iodine-magnesium exchange reaction of 2-iodo-1,4-phenylenediamine. The corresponding 2-magnesiated-1,4-phenylenediamine derivatives can be transmetallated either to copper: · a subsequent allylation reaction furnishes the allylated products in good yield, or to the corresponding zinc reagents: · a subsequent smooth palladium-catalyzed cross-coupling reaction with a range aryl iodides furnishes the polyfunctionalized cross-coupling products in good yield, · this cross-coupling reaction is highly tolerant towards electronic as well as steric effects.
abstract: In summary, reaction conditions have been found for a versatile nickel-catalyzed crosscoupling reaction in the presence of an electron deficient styrene promoter, allowing for the first time: · effective coupling of readily available functionalized alkylzinc halides and benzylic zinc bromides with functionalized alkyl iodides in the presence of TBAI · the application of alkyl bromides in a Csp3-Csp3 cross-coupling reaction. Furthermore, · the presence of sensitive functional groups such as an amino function with an unprotected NH group is tolerated · coupling of diastereomerically enriched zinc reagents proceed with high retention of configuration at the zincated carbon · scaling up can be achieved without significant loss of chemical yield. In summary, an effective and high yielding protection-deprotection protocol has been developed for the iodine-magnesium exchange reaction of 2-iodo-1,4-phenylenediamine. The corresponding 2-magnesiated-1,4-phenylenediamine derivatives can be transmetallated either to copper: · a subsequent allylation reaction furnishes the allylated products in good yield, or to the corresponding zinc reagents: · a subsequent smooth palladium-catalyzed cross-coupling reaction with a range aryl iodides furnishes the polyfunctionalized cross-coupling products in good yield, · this cross-coupling reaction is highly tolerant towards electronic as well as steric effects.
author: Jensen, Anne Eeg
date published: 2001-11-22
date modified: 2026-07-24T02:51:27Z
provider: Ludwig Maxmilians Universität München
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Ludwig-Maximilians-Universität