Palladium-Catalyzed Cross-Coupling Reactions in One-Pot Multicatalytic Processes
作者:Hélène Lebel、Chehla Ladjel、Lise Bréthous
DOI:10.1021/ja0733235
日期:2007.10.1
Palladium-catalyzedcross-couplingreactions have been investigated in multicatalytic processes to synthesize disubstituted alkenes and alkanes from carbonyl derivatives. The use of copper-catalyzed methylenation reactions is the key starting reaction to produce terminal alkenes which are not isolated, but submitted to further structure elongation. Not only is the isolation of the alkene intermediate
4-Phenol diazoniumsalts undergo Pd-catalyzed Heck reactions with various styrenes to 4′-hydroxy stilbenes. In almost all cases higher yields and fewer side products were observed, compared to the analogous 4-methoxy benzene diazoniumsalts. In contrast, the reaction fails completely with 2- and 3-phenol diazoniumsalts. For these substitution patterns the methoxy-substituted derivatives are superior
Stereospecific Iron-Catalyzed Carbon (sp<sup>2</sup>)–Carbon (sp<sup>2</sup>) Cross-Coupling of Aryllithium with Vinyl Halides
作者:Peng Chen、Zhi-Yong Wang、Xiao-Shui Peng、Henry N.C. Wong
DOI:10.1021/acs.orglett.1c01318
日期:2021.6.4
We present herein an efficient synthetic protocol involving iron-catalyzed cross-coupling of organolithium compounds with vinyl halides as key coupling partners. More than 30 examples were obtained with moderate to good yields and high stereoselectivities. The practicality of this method is evidenced by a gram-scale synthesis. In addition, a preliminary mechanistic investigation was also performed
A nickel-catalyzed cross-coupling of alkenyl methyl ethers with Grignard reagents, undermildconditions, is described. These conditions allowed access to various stilbenes and heterocyclic stilbenic derivatives as well as to a potential anticancer agent DMU-212.
Stereoselective Peterson Olefinations from Bench-Stable Reagents and<i>N</i>-Phenyl Imines
作者:Manas Das、Atul Manvar、Maïwenn Jacolot、Marco Blangetti、Roderick C. Jones、Donal F. O'Shea
DOI:10.1002/chem.201500475
日期:2015.6.8
The synthesis of bench‐stable α,α‐bis(trimethylsilyl)toluenes and tris(trimethylsilyl)methane is described and their use in stereoselective Peterson olefinations has been achieved with a wide substrate scope. Product stereoselectivity was poor with carbonyl electrophiles (E/Z ∼1:1 to 4:1) though this was significantly improved by employing the corresponding substituted N‐benzylideneaniline (up to 99:1)