Palladium Catalyzed Aryl Amine Formation Using Cobalt-containing Bulky Phosphine Ligands

• Main Authors: Jian-Cheng Lee, 李堅呈
• Other Authors: Fung-E Hong
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/96191169010019946850

碩士 === 國立中興大學 === 化學系 === 93 === Aromatic amines play a key role in a number of fields. These include pharmaceuticals, agrochemicals, photography, xeroxography, pigments and electronic materials. One of the most revealing facts is that in 1994’s list of the twenty top-selling pharmaceuticals, a significant number contained aromatic carbon-nitrogen bonds. We use Dewar-Chatt-Duncanson’s Model principle, and develop several dicobalt-containing phosphine ligands. The applications of these ligands in the amination reactions were pursued. Palladium catalyzed amination reactions using bromobenzene and morpholine as reaction substrates, were carried out by employing the cobalt-containing phosphine ligand 1 chelated palladium complex. It was found that in the case of 1:Pd(OAc)2 the performance is better with the ratio of 1:1 than 2:1. A novel palladium complex, [1-H+]-Pd(OAc) 2, was obtained from the reaction of a dicobalt-containing mono-phosphine ligand, [(-PPh2CH2PPh2) Co2(CO)4][-PhC≡CP(t-Bu)2] 1 with Pd(OAc)2. As revealed by the crystal structure, a process of ortho-metallation took place and presumably accompanied by the release of one equivalent of acetic acid. 2 is a stable compound and is not regarded as the active species in amination reactions.