The Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, People's Republic of China.
Dalton Trans. 2012 Oct 14;41(38):11597-607. doi: 10.1039/c2dt30931a. Epub 2012 Aug 17.
A series of bis(phenol)-functionalized imidazolium salts, 1,3-bis(4,6-di-R(1)-2-hydroxybenzyl)-2-R(2)-4,5-di-R(3)-imidazolium chlorides H(3)L(n)Cl (R(1) = (t)Bu, R(2) = R(3) = H, H(3)L(1)Cl, 1; R(1) = CH(3), R(2) = R(3) = H, H(3)L(2)Cl, 2; R(1) = (t)Bu, R(2) = H, R(3) = Cl, H(3)L(3)Cl, 3; R(1) = (t)Bu, R(2) = CH(3), R(3) = H, H(3)L(4)Cl, 4), were used to produce a novel series of ionic iron(III) complexes [H(3)L(n)][FeX(4)] (n = 1, X = Cl, 5; n = 2, X = Cl, 6; n = 3, X = Cl, 7; n = 4, X = Cl, 8; n = 1, X = Br, 9; n = 3, X = Br, 10). All of the complexes were characterized by Raman spectroscopy and electrospray ionization mass spectrometry. Elemental analysis and X-ray crystallography were also used. All of the complexes were non-hygroscopic and air-stable, with five of them existing as solids (5, 7-10) and one as an oil (6) at room temperature. A preliminary catalytic study on the cross-coupling reactions of aryl Grignard reagents with primary and secondary alkyl halides bearing β-hydrogens, revealed that all of the ionic iron(III) complexes exhibited good to excellent catalytic activity. Complexes 5, 6 and 8 exhibited optimal activity, whereas 7, 9 and 10 showed only moderate activity. Furthermore, by simply decanting the cross-coupling product in the ether layer, complexes 5 and 6 could be reused in at least seven successive runs without significant loss in catalytic activity.
一系列双（酚）-功能化的咪唑鎓盐，1,3-双（4,6-二-R(1)-2-羟苄基）-2-R(2)-4,5-二-R(3)-咪唑鎓氯化物 H(3)L(n)Cl（R(1) = (t)Bu，R(2) = R(3) = H，H(3)L(1)Cl，1；R(1) = CH(3)，R(2) = R(3) = H，H(3)L(2)Cl，2；R(1) = (t)Bu，R(2) = H，R(3) = Cl，H(3)L(3)Cl，3；R(1) = (t)Bu，R(2) = CH(3)，R(3) = H，H(3)L(4)Cl，4），被用于合成一系列新型的离子铁（III）配合物[H(3)L(n)][FeX(4)]（n = 1，X = Cl，5；n = 2，X = Cl，6；n = 3，X = Cl，7；n = 4，X = Cl，8；n = 1，X = Br，9；n = 3，X = Br，10）。所有的配合物都通过拉曼光谱和电喷雾质谱进行了表征。还使用了元素分析和 X 射线晶体学。所有的配合物都是非吸湿性的，在空气中稳定，其中五个为固体（5、7-10），一个为油（6），在室温下存在。对芳基格氏试剂与带有β-氢的伯烷基和仲烷基卤化物的交叉偶联反应的初步催化研究表明，所有的离子铁（III）配合物都表现出良好到优异的催化活性。配合物 5、6 和 8 表现出最佳的活性，而 7、9 和 10 则表现出中等活性。此外，通过简单地在乙醚层中倾析交叉偶联产物，配合物 5 和 6 可以在至少七个连续循环中重复使用，而催化活性没有明显损失。
