Palladium-catalyzed synthesis of terminal acetalsvia highly selective anti-Markovnikov nucleophilic attack of pinacol on vinylarenes, allyl ethers, and 1,5-dienes
A palladium-catalyzed reaction of vinylarenes, allyl ethers, and 1,5-dienes with pinacol proceeded via a selective anti-Markovnikov nucleophilic attack to afford corresponding terminal acetals as major products. The bulkiness of pinacol was found to be critical in controlling the regioselectivity.
Catalytic migratory oxidative coupling of nitrones through an outer-sphere C(<i>sp<sup>3</sup></i>)-H activation process
作者:Shogo Hashizume、Kounosuke Oisaki、Motomu Kanai
DOI:10.1002/tcr.201100024
日期:2011.9.29
efficient C‐Hactivation, which has attracted increased interest in organic chemistry. In this account, we describe a CuI‐catalyzed oxidative coupling between nitrones and various ethers or amines as an example. Predictable site‐selective C‐C bond formation was achieved throughactivation of the C‐H bonds in each coupling partner and the migration of a C‐N double bond. Mechanisticstudies strongly suggested
Functional‐Group‐Tolerant Catalytic Migratory Oxidative Coupling of Nitrones
作者:Shogo Hashizume、Kounosuke Oisaki、Motomu Kanai
DOI:10.1002/asia.201200359
日期:2012.11
A copper‐catalyzed migratory oxidative‐coupling reaction between nitrones and various ethers/amines exhibited high functional‐group tolerance. Even in aqueous media, the reaction proceeded efficiently. For practical use of this catalysis, a unique sequential Huisgen cycloaddition was demonstrated. Mechanistic investigations revealed that the reaction proceeded through oxidative catalytic activation
Catalytic Migratory Oxidative Coupling of Nitrones
作者:Shogo Hashizume、Kounosuke Oisaki、Motomu Kanai
DOI:10.1021/ol201629n
日期:2011.8.19
bond-formation proceeds through cleavage of two C(sp3)–H bonds concomitant with C═N double bond-migration. The reaction provides an alternating nitrone moiety, allowing for further synthetically useful transformations. Radical clock studies suggest that the nucleophilicaddition of nitrones to an oxidatively generated carbocation is a key step.