Summary: | 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.
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