This thesis is composed of two parts. The palladium-catalysted synthesis of 2-arylphenols and carbazoles via carbon-hydrogen (C-H) bond activation is described. Treatment of 2-phenoxypyridines with two and a half equivalents of potassium aryltrifluoroborate and 10 mol % of Pd(OAc)2 in the presence of two equivalents of Ag2CO3, one equivalent of p-benzoquinone (BQ), and four equivalents of DMSO with (or without) H2O at 130-140 oC for 48 h in dried CH2Cl2 gave the ortho-arylated 2-phenoxypyridines in modest to excellent yields. The investigation of kinetic isotope effect (kH/kD) is determined to be 5.25, which indicates that C-H bond cleavage occurs in the rate-determining step. 2-(Biphenyl-2-yloxy)pyridines was treated with methyl trifluoromethanesulfonate and subsequently sodium methoxide to give the 2-arylphenols to demonstrate the pyridine is a removable directing group. On the other hand, a novel one-pot synthesis for N-pyridylcarbazoles by the reaction of N-phenylpyridin-2-amines with potassium aryltrifluoroborates using Pd(OAc)2 as the catalyst is presented. For instance, reaction of N-phenylpyridin-2-amines with four equivalents of potassium aryltrifluoroborate under the optimal reaction condition gave N-pyridylcarbazoles in 67% yield along with N-(biphenyl-2-yl)pyridin-2-amine in 13% yield. The investigation of kinetic isotope effect (kH/kD) for first C-H bond activation/C-C bond formation step is determined to be 2.14, and that of the second C-H bond activation/C-N bond formation steps is 1.18. On the basis of KIE analysis, it might indicate that first C-H activation undergo direct C-H bond cleacage, and second step should be via electrophilic aromatic substitution.
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0706111-184923 |
| Date | 06 July 2011 |
| Creators | Lin, Pi-shan |
| Contributors | Ming-Jung Wu, Chiang, Michael Yen-Nan, Chin-Hsing Chou |
| Publisher | NSYSU |
| Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
| Language | Cholon |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0706111-184923 |
| Rights | restricted, Copyright information available at source archive |
Page generated in 0.0018 seconds