Study of Synthesis, Characterization and Reactivity of Fluorenyl Aluminum(III) Complexes

• Main Authors: Hwang, Robin Christine, 黃珞蕎
• Other Authors: Liu, Hsueh-Ju
• Format: Others
• Language: en_US
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/c964q8

碩士 === 國立交通大學 === 應用化學系碩博士班 === 107 === The motivation of this research is to synthesize the low-valent aluminum complexes supported by 2,7-di-tert-butyl-9H-fluorenyl ligand. FluoAlCl2(OEt2) (2, Fluo=ditbutylfluorenyl) was first synthesized then reduced by KC8 (potassium graphite) to form Fluo2AlCl(OEt2) (3), [Fluo3AlKCl(OEt2)] (4) and Fluo3Al(OEt2) (5). Another strategy was taken to synthesize a group of tris-fluorenyl ligands: H3L1 and H3L2. Numerous amides were mixed with 2 to form FluoAlCl(N(SiMe3)2)(THF) (6) FluoAl(N(SiMe3)2)2 (7), FluoAlCl(NiPr2)(OEt2) (8) and FluoAl(NHDipp)2(OEt2) (9). Bulky NHC (N-heterocyclic) carbene like IMes (1,3-bis(2,4,6 trimethylphenyl)imidazolylidene) and IPr (1,3-Bis-(2,6-diisopropylphenyl)imidazole-ylidene) were also mixed with 2 to form FluoAl(IMes)Cl2 (10) and FluoAl(IPr)Cl2 (11). FluoAlH2(OEt2) (12) was formed by mixing 3 with one equiv. of LAH (lithium aluminum hydride). FluoAl(dmap)H2 (13, dmap = 4-dimethylaminopyridine) was then synthesized by mixing 12 with one equiv. of dmap. Reduction of 6, 7, 8 and 9 using KC8 resulted in a group of unclean spectra. KFluo, the potassium salt and an unidentified Al(NHC) species were found after the KC8 reduction of 10 and 11. 13 tended to release free ditbutylfluorene (1) upon heating, likely resulting from reductive elimination at Al center.