共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
3.
4.
5.
6.
7.
8.
BinFU DaMingDU QingXIA 《中国化学快报》2004,15(4):383-385
The synthesis of bis(oxazoline) dicarboxylate derivatives was investigated.Diethyl-aminosulfur trifluoride (DAST) was used as a convenient cyclization reagent in the synthesis of bis(oxazoline) dicarboxylate derivatives,which can not be obtained by the general method using MsC1 and Et3N as dehydrating cyclization reagent. 相似文献
9.
Hiroya Takada Yoshiaki Nishibayashi Kouichi Ohe Sakae Uemura 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):363-364
Prochiral sulfides reacted with Phl=NTs in the presence of a catalytic amount of Cu(I) salt together with a chiral 4,4′-disubstituted bis(oxazoline) ligand to afford the corresponding chiral sulfimides. 相似文献
10.
The electron impact mass spectra of ten new C2-symmetric chiral bis(oxazoline) and bis(thiazoline) have been studied. Bis(thiazoline) and bis(oxazoline) possess the same fragmentation mechanism under EI conditions. An unusual fragmentation pathway has been found in the compounds studied. Due to the presence of phenyl group, compounds 6 and 10 undergo a new fragmentation pathway except for the common way as the other eight compounds.Mass analyzed ion kinetic energy spectra experiments and high resolution accurate mass measurement were conducted to confirm the proposed fragmentation pathways. 相似文献
11.
Chiral bis(oxazoline) ligands have been applied in many enatioselective reactions. Recently, studies of the immobilization of bis(oxazoline) on both soluble and insoluble supports have been of great interest. Among the different methods to anchor the homogeneous catalysts, a soluble, polymer-supported catalyst usually achieves higher stereoselectivity and activity because the catalysis can be separated and recycled via simple methods such as solvent precipitation. Dendrimers are highly branche… 相似文献
12.
A novel chiral bis(ferrocenyl) P2N ligand 1 with C2-symmetry was synthesized through a four-step procedure from (R)-N,N-dimethyl-l-ferrocenylethylamine. In a model reaction of Pdcatalyzed allylic alkylation of 1,3-diphenylprop-2-enyl acetate 6 with dimethyl malonate, good enantioselectivity (86% e.e.) was obtained. 相似文献
13.
14.
15.
Bai-Yuan YangXiao-Min Chen Guo-Jun DengYi-Li Zhang Qing-Hua Fan 《Tetrahedron letters》2003,44(17):3535-3538
A series of copper(II) complexes, with chiral bis(oxazoline) ligands disubstituted at the carbon atom linking the two oxazolines by Fréchet-type polyether dendrimers, have been designed and synthesized. These complexes were used as Lewis acid catalysts in enantioselective aldol reactions in aqueous media. Good yields and moderate enantioselectivities were achieved, which are comparable with those resulting from the corresponding smaller catalysts. 相似文献
16.
17.
A series of novel chiral C2-symmetric bis (oxazoline) ligands have been synthesized.The copper and magnesium complexes,prepared in situ from copper(Ⅱ)-triflate of magnesium triflate with the new enantiopure oxazoline ligands,were evaluated as chiral catalysts in the enantioselective Diels-Alder reaction of cyclopentadiene with N-crotenoyl-oxazolidin-2-one.Primary results showed that diastereoselectivity up to 94% and enantioselectivity up to 68% ee for endo products were observed respectively with these ligands. 相似文献
18.
手性二噁唑啉吡啶铁和镍配合物的制备与表征 总被引:1,自引:0,他引:1
Tridentate bis(oxazolinylpyridine)(1) reacted with nickel chloride or ferrous chloride in anhydrous ethanol to form bis(oxazolinylpyridine) Nickel(Ⅱ) and Iron(Ⅱ) complexes. The stable solid complexes were characterized with IR, UV, MS, XPS and elemental analysis. No stable complexes were formed with bidentate bis(oxazoline)(2) ins- tead of bis(oxazolinylpyridine). 相似文献
19.
20.
改进了邻溴苯基-2-(口恶)唑啉的合成方法,使得N-(β-羟乙基)-2-(口恶)溴苯甲酰胺在氯化亚砜作用下缩合成唑啉的收率从40%左右提高到84%,并避免了使用NaH试剂,为芳基-2-(口恶)唑啉的合成提供一条方便、经济的路线.实验结果表明,反应温度对唑啉的收率的影响显著,随着反应温度的升高收率明显降低,室温下几乎得不到目标产物.根据实验结果推测其反应过程是经过互变异构酰亚胺中间物Ⅰ进行的. 相似文献