Regioselective Asymmetric Allylic Alkylation Reaction ofα-Cyanoacetates Catalyzed by a Heterobimetallic Platina-/Palladacycle
| Autor: | Marcel Weiss, Julia Holz, René Peters |
|---|---|
| Rok vydání: | 2015 |
| Předmět: |
Substitution reaction
Allylic rearrangement 010405 organic chemistry Chemistry Stereochemistry Organic Chemistry Regioselectivity 010402 general chemistry 01 natural sciences Medicinal chemistry Oxidative addition 0104 chemical sciences Stereocenter Tsuji–Trost reaction Nucleophile SN2 reaction Physical and Theoretical Chemistry |
| Zdroj: | European Journal of Organic Chemistry. 2016:210-227 |
| ISSN: | 1434-193X |
| DOI: | 10.1002/ejoc.201501290 |
| Popis: | Allylic substitution reactions provide a valuable tool for the functionalization of CH acidic pronucleophiles. Often, control over the stereocenter generated at the nucleophilic reactant is still a challenge. The majority of studies that address this issue employ metal complexes with a low metal oxidation state (e.g. Pd0) to form allyl complexes through oxidative addition. In this article we describe the use of heterobimetallic PtII/PdII complexes, which probably activate the olefinic substrates through an SN2′ pathway. The reaction of α-cyanoacetates delivers linear allylation products with exclusive regioselectivity and high E/Z-selectivity for the new C=C double bond. Although the enantioselectivities attained are moderate, they are significantly higher than with related mono-PdII or -PtII catalysts or the corresponding bis-PdII complex, which indicates cooperation of the different metals. Control experiments suggest simultaneous activation of both reaction partners. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text