Structural and Synthetic Insights into Pyridine Homocouplings Mediated by a β-Diketiminato Magnesium Amide Complex
作者:Laia Davin、William Clegg、Alan R. Kennedy、Michael R. Probert、Ross McLellan、Eva Hevia
DOI:10.1002/chem.201803297
日期:2018.10.1
The reaction of [(DippNacnac)Mg(TMP)] (1) with 4‐subtituted pyridines proceeds via sequential regioselective metallation and 1,2‐addition to furnish a range of symmetric 4,4′‐R2‐2,2′‐bipyridines in good yield, representing a new entry into bipyridine synthesis. Interestingly, the reaction of 1 with 2‐OMe‐pyridine led to formation of asymmetric bipyridine 6, resulting from the C6‐magnesiation of the
An efficient and new protocol for phosphine-free Suzuki coupling reaction using palladium-encapsulated and air-stable MIDA boronates in an aqueous medium
作者:Joaquim Fernando Mendes da Silva、Andres Felipe Yepes Perez、Natália Pinto de Almeida
DOI:10.1039/c4ra03586k
日期:——
A simple methodology for Suzuki–Miyaura cross-coupling reactions using microencapsulated palladium and (het)aryl MIDA boronates in water–alcohol under phosphine-free conditions was developed.
Synthesis of 2,2′-Bipyridines via Suzuki-Miyaura Cross-Coupling
作者:Arne Lützen、Christoph Gütz
DOI:10.1055/s-0029-1217082
日期:2010.1
For a long time, the Suzuki-Miyauracross-couplingreaction could not be used for the synthesis of 2,2′-bipyridines due to the lack of sufficiently stable 2-pyridylboron compounds. Stabilized 2-pyridylboronic acid esters recently developed by Hodgson, however, were found to be ideally suited for this purpose. Two general protocols could be developed and demonstrated to be valuable alternatives, which
Homoleptic lithium tri‐ and tetraalkyl zincates were reacted with a set of bromopyridines. Efficient and chemoselective bromine–metal exchanges were realized at roomtemperature with a substoichiometric amount of nBu4ZnLi2⋅TMEDA reagent (1/3 equiv; TMEDA=N,N,N′,N′‐tetramethylethylenediamine). This reactivity contrasted with that of tBu4ZnLi2⋅TMEDA, which was inefficient below one equivalent. DFT calculations
Phosphine-Free Suzuki Cross-Coupling Reaction Using an Efficient and Reusable Pd Catalyst in an Aqueous Medium Under Microwave Irradiation
作者:Joaquim F. M. da Silva、Andres F. Yepes Perez、Natália P. de Almeida
DOI:10.1080/00397911.2015.1057289
日期:2015.9.2
Abstract We report here an improved, highly efficient, and general method for the ligand-free Suzuki cross-couplingreaction to the synthesis of biaryls, bipyridyls, thienylpyridine, and allylphenols. Microwaveirradiation of (het)aryl halides and (hetaryl, allyl)arylboronic acid N-methyl-iminodiacetic acid (MIDA) ester, using polyurea microencapsulated palladium catalyst (Pd EnCat 30), gave the coupling