(S)-5,5’-二溴-6,6'-二(4-三氟甲基苯基)-2,2’-联萘酚与(S)-5,5’-二乙炔基-6,6’-二丁基-2,2’-二丁氧基-1,1’-联萘酚通过Pd催化的Sonogashira反应合成了-种新的手性线性高分子聚合物,研究了这种高分子在Et2zn不对称醛加成反应中的应用.结果表明这种高分子在Ti(0iPr)。的存在条件下展示了良好的反应活性.而且,这种高分子配体在循环利用10次后可仍然保持较好的活性.
A new linear chiral polymer ligand was synthesized by the polymerization of (S)-5,5'- dibromo-6,6'-di ( 4-trifluoromethylphenyl ) -2,2'-binaphthol ( S-M-1 ) with (S) -5,5'-diethynyl-6,6'- dibutyl-2, 2'-dibutoxy-1, l'-binaphthyl ( S-M-2 ) via Pd-catalyzed Sonogashira reaction. The application of the chiral polymer ligand in the asymmetric addition of Et2Zn to various aromatic aldehydes had been studied. The results showed that this kind of soluble chiral polybinaphthols ligand in combination with Ti( Oipr)4 could exhibit good reactivity and enantioselectivity for the asymmetric addition of Et2Zn to aromatic aldehydes. Moreover, the chiral polymer ligand showed superior enantioselectivity over the model compound S-1 and could keep similar reactivity as well as enantioselectivity after ten recycles.