Palladium-Catalyzed Benzylation of Heterocyclic Aromatic Compounds
作者:David Lapointe、Keith Fagnou
DOI:10.1021/ol901689q
日期:2009.9.17
Broadly applicable palladium-catalyzed heteroarene benzylation reactions are described with a focus on the most challenging heterocyclic classes under traditional benzylation techniques such as sulfur-containing heterocycles and those bearing functional groups that would be incompatible with reactions requiring Lewis acids and/or strong bases.
Suzuki-Miyaura Cross-Couplings
Mediated by <i>trans</i>-PdBr(<i>N</i>-Succ)(PPh<sub>3</sub>)<sub>2</sub>: A
Convenient Synthetic Method for Diarylmethanes and Aryl(heteroaryl)methanes
作者:Ian Fairlamb、Richard Taylor、Petr Sehnal
DOI:10.1055/s-0028-1083293
日期:——
Diarylmethanes can be accessed efficiently by Suzuki-Miyauracross-couplings of arylboronic acids with benzyl halides mediated by trans-PdBr(N-Succ)(PPh3)2. The methodology can be applied to the synthesis of aryl(heteroaryl)methanes. catalysis - palladium - pseudohalide - phosphine
Base cleavage of substituted [phenyl(2-thienyl)methyl]- and [phenyl(2-furyl)methyl]-trimethylsilane. Stabilization of carbanionic centres by 2-thienyl and 2-furyl groups
Ph(2-furyl)CH2, 29.6; (2-thienyl)2CH2, 27.1. The effect of the 2-Cl substituent in the thiophen ring is close to that of the p-Cl substituent in the benzene ring, and the effects of the p-Me substituents on the benzene ring are very close to those of the 2-Me substituents on the thiophen or furan rings. The product and rate isotope effects (determined by use of MeOD) are consistent with separation of the
Simple Palladium(II) Precatalyst for Suzuki−Miyaura Couplings: Efficient Reactions of Benzylic, Aryl, Heteroaryl, and Vinyl Coupling Partners
作者:Michael J. Burns、Ian J. S. Fairlamb、Anant R. Kapdi、Petr Sehnal、Richard J. K. Taylor
DOI:10.1021/ol702291r
日期:2007.12.1
trans-PdBr(N-Succ)(PPh3)(2) (1) is a universally effective precatalyst for Suzuki-Miyaura cross-couplings of benzylic halides with aryl- or heteroarylboronic acids. Substituted aryl halides and halogenated cyclic enones can be cross-coupled with aryl- or vinylboronic acids in excellent yields. Catalyst recycling is also demonstrated.
Alternative Approach toward the Generation of Benzylic Zinc Reagent: Direct Oxidative Addition of Active Zinc into the Carbon–Oxygen Bond of Benzyl Mesylates