55554-09-1Relevant academic research and scientific papers
Sterically hindered (pyridyl)benzamidine palladium(II) complexes: Syntheses, structural studies, and applications as catalysts in the methoxycarbonylation of olefins
Akiri, Saphan O.,Ojwach, Stephen O.
, (2021/09/09)
Reactions of ligands (E)-N′-(2,6-diisopropylphenyl)-N-(4-methylpyridin-2-yl)benzimidamide (L1), (E)-N′-(2,6-diisopropylphenyl)-N-(6-methylpyridin-2-yl)benzimidamide (L2), (E)-N′-(2,6-dimethylphenyl)-N-(6-methylpyridin-2-yl)benzimidamide (L3), (E)-N′-(2,6-dimethylphenyl)-N-(4-methylpyridin-2-yl)benzimidamide (L4), and (E)-N-(6-methylpyridin-2-yl)-N′-phenylbenzimidamide (L5) with [Pd(NCMe)2Cl2] furnished the corresponding palladium(II) precatalysts (Pd1–Pd5), in good yields. Molecular structures of Pd2 and Pd3 revealed that the ligands coordinate in a N^N bidentate mode to afford square planar compounds. Activation of the palladium(II) complexes with para-tolyl sulfonic acid (PTSA) afforded active catalysts in the methoxycarbonylation of a number of alkene. The resultant catalytic activities were controlled by the both the complex structure and alkene substrate. While aliphatic substrates favored the formation of linear esters (>70%), styrene substrate resulted in the formation of predominantly branched esters of up to 91%.
Pd-Catalyzed Regioselective Alkoxycarbonylation of 1-Alkenes Using a Lewis Acid [SnCl2 or Ti(OiPr)4] and a Phosphine
Amézquita-Valencia, Manuel,Achonduh, George,Alper, Howard
, p. 6419 - 6424 (2015/06/30)
The phosphine ligand mediated palladium catalyzed alkoxycarbonylation of alkenes was investigated with the objective of attaining good linear selectivity for the ester. The effect of various parameters such as solvents, additives, palladium precursors, CO pressures, and alkenes of various structural complexities were examined. The results revealed the importance of using a Lewis acid such as SnCl2 or Ti(OiPr)4 in combination with a monodentate ligand such CYTOP 292 or P(p-anisyl)3 to enhance the regioselectivity for the linear isomers in the range of 70-96%.
Highly regioselective anti-markovnikov palladium-borate-catalyzed methoxycarbonylation reactions: Unprecedented results for aryl olefins
Vieira, Tiago O.,Green, Mike J.,Alper, Howard
, p. 6143 - 6145 (2007/10/03)
(Chemical Equation Presented) A general, highly efficient and regioselective methoxycarbonylation, by means of a palladium-salicylicborate- catalyzed protocol, of terminal alkyl and aryl olefins is described. The substrates include aliphatic alkenes, allylbenzenes, and styrene derivatives. The yields are very good (60-92%) and the regioselectivity, in favor of the linear ester, is up to quantitative - unprecedented in the case of styrenes.
Tandem isomerisation-carbonylation catalysis: Highly active palladium(II) catalysts for the selective methoxycarbonylation of internal alkenes to linear esters
Pugh,Drent,Pringle
, p. 1476 - 1477 (2007/10/03)
Fast, selective conversion of internal olefins to linear esters is catalysed by Pd(II) complexes of chelating bis (phosphaadamantyl)diphosphines and the catalysis is acutely sensitive to the ligand backbone and even to the diastereomer used; the results are compared with those for the PBut2 analogue.
Selective Mono- and Bis(alkoxycarbonylation)s of Olefins Catalyzed by Palladium in the Presence of Cu(I) or Cu(II) Chloride under Remarkably Mild Conditions. Application to the Synthesis of γ-Butyrolactone Derivatives
Toda, Shiho,Miyamoto, Masanori,Kinoshita, Hideki,Inomata, Katsuhiko
, p. 3600 - 3606 (2007/10/02)
Palladium-catalyzed mono- and bis(alkoxycarbonylation)s of the olefins were controlled by the use of copper(II) and copper(I) chloride, respectively, in alcohol under normal pressure of carbon monoxide and oxygen at room temperature without any other additives. 3-Buten-1-ols gave the corresponding γ-butyrolactones and 2-oxotetrahydrofuran-3-acetic acid esters, respectively, in high yields.
