Nickel-Phosphine Complex-Catalyzed Grignard Coupling. I. Cross-Coupling of Alkyl, Aryl, and Alkenyl Grignard Reagents with Aryl and Alkenyl Halides: General Scope and Limitations
(s)), aryl, and alkenyl Grignard reagents and nonfused, fused, and substituted aromatic halides and haloolefins. Limitations lie in sluggish reactions between alkyl Grignard reagents and dihaloethylenes. The most effective catalysts are [Ni(C6H5)2P(CH2)3P(C6H5)2}Cl2] for alkyl and simple aryl Grignard reagents, [Ni(CH3)2P(CH2)2P(CH3)2}Cl2] for alkenyl and allylic Grignard reagents and [NiP(C6H5)3}2-Cl2]
Nickel-catalyzed cross-coupling of aryl phosphates with grignard and organoaluminium reagents. Synthesis of alkyl-, alkenyl-, and arylbenzenes from phenols
Aryl phosphates derived from phenols were converted into alkyl-, alkenyl-, and aryl- benzenes in high yields by cross-coupling with various kinds of Grignard and organoaluminium reagents in the presence of nickel (II) catalysts.
Murahashi Cross‐Coupling at −78 °C: A One‐Pot Procedure for Sequential C−C/C−C, C−C/C−N, and C−C/C−S Cross‐Coupling of Bromo‐Chloro‐Arenes
作者:Narayan Sinha、Dorus Heijnen、Ben L. Feringa、Michael G. Organ
DOI:10.1002/chem.201901678
日期:2019.7.11
The coupling of organolithium reagents, including strongly hindered examples, at cryogenic temperatures (as low as −78 °C) has been achieved with high‐reactivity Pd‐NHC catalysts. A temperature‐dependent chemoselectivity trigger has been developed for the selective coupling of arylbromides in the presence of chlorides. Building on this, a one‐pot, sequential coupling strategy is presented for the
Benzylic Grignard reagents: application of [Mg(anthracene)(thf)<sub>3</sub>](thf = tetrahydrofuran) in regioselective Grignard formation and C–O cleavage in benzyl ethers
作者:Michael J. Gallagher、Stephen Harvey、Colin L. Raston、Rodney E. Sue
DOI:10.1039/c39880000289
日期:——
Benzylic Grignardreagents (2)–(4), bearing ortho- and para-halogeno ring substituents, are readily accessible by treating the corresponding benzylic halide with [Mg(anthracene)(thf)3](1) in tetrahydrofuran (thf); o- and p-chloromethyl(methoxymethyl)benzenes with (1) rapidly yield ‘di-Grignards’ whereas the meta-isomer only affords a mono-Grignard' (5), and bis(methoxymethyl)benzenes slowly undergo
Di(lithiomethyl)benzenes from di(chloromethyl)benzenes by a DTBB-catalysed lithiation under Barbier-type conditions
作者:Cecilia Gómez、Fernando F Huerta、Miguel Yus
DOI:10.1016/s0040-4020(97)00878-8
日期:1997.10
The reaction of 1,2-, 1,3- and 1,4-di(chloromethyl)benzenes (1a-c) and different electrophiles [PriCHO, ButCHO, PhCHO, (CH2)5CO, PhCOMe, Me3SiCl] with an excess of lithium powder and a catalytic amount of DTBB (4 mol%) in THF at 0°C leads, after hydrolysis with water, to the expected dioles or disilylated compounds 2aa-cf.