The application of vanadium in organic catalytic reaction

• Main Authors: der-ren hwang, 黃德仁
• Other Authors: biing-jiun uang
• Format: Others
• Language: zh-TW
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/49835618999937802679

博士 === 國立清華大學 === 化學系 === 87 === The catalytic applications of V(IV) and V(V) ions in organic transformations have been discussed. The thesis is divided into three parts. In the first part VO(acac)2 and VO(salen) catalyzed oxidations in the presence of molecular oxygen have been presented. The oxidative coupling of 2-naphthol to BINOL, phenol and its derivatives to the corresponding biphenols and the oxidation of p-hydroquinones to p-quinones were carried out successfully in good yields. However, selectivities in the asymmetric coupling reactions were not up to the expected level. The conditions have to be improved for better selectivities. The synthesis of a series of tridentate ligands 100-108 from camphor and their vanadium complexes for asymmetric oxidation of sulfide to sulfoxide have been described in Part 2. The best results were obtained when the ligand 105 was used. The maximum optical induction (66 %) was achieved for the oxidation of sulfide 113 to sulfoxide 118. In Part 3, VO(acac)2 was used to activate tertiary amine N-oxide by generating iminium ion for subsequent nucleophilic addition to form C-C bond. This methodology was applied in Mannich reaction and the synthesis of a-arylamines and a-cyanoamines.