Catalytic hydrogenation of aromatic hydrocarbons. Stereochemical definition of the catalytic cycle for .eta.3-C3H5Co(P(OCH3)3)3
作者:J. R. Bleeke、E. L. Muetterties
DOI:10.1021/ja00393a011
日期:1981.2
The eta/sup 3/-C/sub 3/H/sub 5/Co(P(OCH/sub3/)/sub3/)/sub 3/-catalyzed hydrogenations with D/sub 2/ of a series of unsaturated organic molecules, including cyclohexenes, cyclohexadienes, and arenes, have been investigated. Complete cis stereoselectivity was observed in the addition of deuterium to the unsaturated ring systems. When alkyl-substituted arenes were reduced with D/sub 2/, the hydrogen
eta/sup 3/-C/sub 3/H/sub 5/Co(P(OCH/sub 3/)/sub 3/)/sub 3/-催化加氢与D/sub 2/一系列不饱和已经研究了有机分子,包括环己烯、环己二烯和芳烃。在向不饱和环系统中加入氘时观察到完全顺式立体选择性。当烷基取代的芳烃用 D/sub 2/ 还原时,只要链中的每个连续碳原子具有至少一个氢原子,烷基链中的氢原子就会发生 HD 交换。因此,广泛的 HD 交换发生在正烷基侧链中,而叔丁基侧链不含氘。当烷基取代的芳烃在烯烃如 1-己烯存在下氢化时,观察到多种异构的烷基环己烯和烯基环己烷。这些异构体物种的相对浓度提供了关于催化循环中(烯烃)钴物种的相对稳定性的信息。从其他竞争性反应,即涉及等摩尔量的两种不同不饱和分子的氢化反应中获得了进一步的机理信息。在对eta/sup 3/-C/sub 8/H/sub 13/Co(P(OCH/sub 3/)/sub
Copper-catalyzed coupling reaction of unactivated secondary alkyl iodides with alkyl Grignard reagents in the presence of 1,3-butadiene as an effective additive
Cu-catalyzed cross-coupling of unactivated secondary alkyl iodides with alkylGrignardreagents in the presence of 1,3-butadiene as a ligand precursor was developed. The use of 1,3-butadiene resulted in improved yields of alkyl-alkyl products with improved selectivities.
The solvent determines the product in the hydrogenation of aromatic ketones using unligated RhCl<sub>3</sub> as catalyst precursor
作者:Soumyadeep Chakrabortty、Nils Rockstroh、Stephan Bartling、Henrik Lund、Bernd H. Müller、Paul C. J. Kamer、Johannes G. de Vries
DOI:10.1039/d1cy01504d
日期:——
Alkyl cyclohexanes were synthesized in high selectivity via a combined hydrogenation/hydrodeoxygenation of aromaticketones using ligand-free RhCl3 as pre-catalyst in trifluoroethanol as solvent. The true catalyst consists of rhodiumnanoparticles (Rh NPs), generated in situ during the reaction. A range of conjugated as well as non-conjugated aromaticketones were directly hydrodeoxygenated to the corresponding