On deprotonation by lithium bistrimethylsilylamide (LBTSA), 2-phthalimidoacetophenone (1) is quantitatively converted to 6H,12H-isoindolo [2,1-a]-6,7a-dihydroxyquinolin-12-one (2); weaker bases proved much less effective. Thermal dehydration of 2 to vinilogous imide 3, then the AlCl3-catalyzed aminolysis by (1S)-arylethylamines afforded (1S)-amides of 2-(2′-carboxyphenyl)-4-hydroxyquinolines (5-7). This sequence represents an efficient assembling of novel chiral heterocycles, potentially useful in enantioselection as ligands or chiral selectors. In situ prepared Pd(II) complexes of 5-7 exhibited catalytic activity in allylic alkylation of 1,3-diphenyl-1-acetoxyprop-2-ene (8) by dimethylmalonate anion; the complex of 7 afforded the highest (64%) enantiomeric excess of 1,3-diphenyl-1-dimetylmalonylprop-2-ene (9).
Studying the effect of morphology on the circularlypolarizedluminescence (CPL) of chiral molecular materials is important for the development of CPL-active materials for applications. Herein, we report that the morphology of Gd(NO3)3/R-,S-AnempH2 [AnempH2 = (1-anthrylethylamino)methylphosphonic acid] assemblies can be controlled by solvent modulation to form spiral bundles Gd(R-,S-AnempH)3·2H2O (R-
研究形貌对手性分子材料圆偏振发光(CPL)的影响对于开发CPL活性材料的应用具有重要意义。在此,我们报道了Gd(NO 3 ) 3 / R -, S -AnempH 2 [AnempH 2 = (1-蒽乙基氨基)甲基膦酸]组装体的形态可以通过溶剂调节来控制,形成螺旋束Gd( R -, S -AnempH) 3 ·2H 2 O ( R -, S -1 )、晶体 Gd( R -, S -AnempH) 3 ·2H 2 O ( R -, S -2 ) 和纺锤形颗粒 Gd( R - , S -AnempH) 3 ·3H 2 O·0.5DMF ( R -, S -3 ) 具有相似的链结构。有趣的是, R - 、 S -1具有 CPL 活性,并且在三对对映体中表现出最高的不对称因子值(| g lum | = 2.1 × 10 –3 ),是R - 、 S的 2.8 倍-2 ,而R -、 S -3则 CPL
Recognition of chiral carboxylates by 1,3-disubstituted thioureas with 1-arylethyl scaffolds
作者:Karla Elisa Trejo-Huizar、Ricardo Ortiz-Rico、María de los Angeles Peña-González、Marcos Hernández-Rodríguez
DOI:10.1039/c3nj00644a
日期:——
Chiral thioureas with 1-arylethyl and 1-arylethyl-2-2-2-trifluoroethyl (Ar = Ph, 1-Napht, 9-Anthr) scaffolds were used as hosts to recognize acetate and chiral mandelates. The higher binding obtained with the trifluoromethyl analogue is also reflected in the higher selectivity factor for one enantiomer. The C2 symmetry was also indispensable to obtain selectivity.
Asymmetric synthesis of the 9-anthracenyl analogues of 1-phenylethylamine and 2,2,2-trifluoro-1-phenylethylamine was achieved via nucleophilic addition to the corresponding N-(tert-butylsulfinyl)imine. amines - asymmetric synthesis - chiral auxiliaries - tert-butanesulfinamide - trifluoromethyl compounds