Part I. Large scale procedure for the α-arylation of esters catalyzed by the pd(i) dimer [p(tbu)3]pd(μ-br)]2. Part II. Palladium-catalyzed γ-arylation of α,β-unsaturated esters

cross-coupling;enolates;homogeneous catalysis;palladium

Huang, David S. ; Hartwig ; John F.

关键词: cross-coupling;    enolates;    homogeneous catalysis;    palladium;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/16816/1_Huang_David.pdf?sequence=2&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

We report the development of a procedure for the α-arylation of esters on 42 mmol scale which did not require use of a glovebox. The coupling of 3-bromoanisole and methyl isobutyrate catalyzed by 0.075 % [(P(tBu)3Pd(μ-Br)]2 occurred in 72% yield. The reaction was performed with commercially available reagents at a lab bench utilizing Schlenk technique. We report the γ-arylation of α,β-unsaturated esters in high yield with broad scope by coupling aryl, heteroaryl and vinyl halides with the corresponding silicon dienolates. These reactions occur in high yield with a variety of esters and with aromatic and vinylic electrophiles bearing potentially reactive functional groups. The coupling also proceeds in moderate to good yield for the coupling with silyl ketene acetals containing substitution at the α,β,γ- or δ-position. Moreover, these reactions occur without typical fluoride activators.