Synthesis, structure and catalytic activity of dicarbene dipalladium complexes with different alkane bridge
作者:Jianfeng Zhao、Long Yang、Kaiqi Ge、Qian Chen、Yongzhong Zhuang、Changsheng Cao、Yanhui Shi
DOI:10.1016/j.inoche.2012.03.041
日期:2012.6
Abstract A series of di-NHC dipalladiumcomplexes Pd2LPy2Cl4 (L = LC3, LC5, LC6 and LC10) with alkyl bridges of different chain lengths were prepared. The molecular structures of Pd2LC3Py2Cl4 (1) and Pd2LC6Py2Cl4 (3) were determined by X-ray diffraction studies. The influence of the different bridges on the structure and reactivity of the complexes was studied. The structure of complex 3 consists of two pseudo-square-planar
Synthesis of stilbene analogues by one-pot oxidation-Wittig and oxidation-Wittig–Heck reaction
作者:Akeel S. Saiyed、Krupa N. Patel、Bola V. Kamath、Ashutosh V. Bedekar
DOI:10.1016/j.tetlet.2012.06.090
日期:2012.8
Synthesis of symmetrical (and unsymmetrical) stilbene derivatives is achieved by a combination of one-pot steps of Kornblum type oxidation of benzyl halide, its simultaneous in situ formation of phosphonium salt, and subsequently their Wittig reaction. In other variant it is oxidized to aldehyde, treated with ylide generated from phosphonium salt (CH3PPh3X) to give styrene, and subjected to Pd catalyzed
triplet energy was greatly improved, and then, it could markedly promote the efficient geometrical isomerization of alkenes from the E-isomer to the Z-isomer. Moreover, it was also effective for energy-transfer-mediated organometallic catalysis, which allowed realization of the cross-coupling of aryl bromides and carboxylic acids through efficient energy transfer from HiBRCP to nickel complexes. Thus, the
A highly selective hydrogenation of alkynesusing an air-stable and readily available manganese catalyst has been achieved. The reaction proceeds under mild reaction conditions and tolerates various functional groups, resulting in (Z)-alkenes and allylic alcohols in high yields. Mechanistic experiments suggest that the reaction proceeds via a bifunctional activation involving metal–ligand cooperativity
Manganese-Catalyzed Cross-Coupling Reaction between Aryl Grignard Reagents and Alkenyl Halides
作者:Gérard Cahiez、Olivier Gager、Fabien Lecomte
DOI:10.1021/ol802273e
日期:2008.11.20
Aryl Grignard reagents react stereospecifically with alkenylhalides in the presence of manganese chloride (10%) to afford good yields of cross-coupling products.