A Circular Dichroism Approach to the Conformation of 1-Arylethylamino-Substituted 1,3,5-Triazine Derivatives
摘要:
CD data of the optically pure 2-[(R)-1-(9-anthryl)ethylamino]-4-chloro-6-[(R)-1-(l-naphthyl)-ethylamino] 2-[(R)-1-(9-anthryl)ethylamino]-4,6-bis[(1-naphthyl)-ethylamino]-1,3,5-triazine, 2,4-bis[(R)-1-(9-anthryl)ethylamino]-6-chloro-1,3,5-triazine are presented. The analysis of the CD spectra by means of the nonempirical DeVoe approach has afforded the complete conformational characterisation of the three s-triazine derivatives, allowing us to establish how the conformation of these derivatives depends on the nature of the substituent 1-arylethylamino groups.
Arynes and Cyclic Alkynes as Synthetic Building Blocks for Stereodefined Quaternary Centers
作者:Elias Picazo、Sarah M. Anthony、Maude Giroud、Adam Simon、Margeaux A. Miller、K. N. Houk、Neil K. Garg
DOI:10.1021/jacs.8b02875
日期:2018.6.20
stereodefined quaternary centers from reactions of arynes and related strained intermediates using β-ketoester-derived substrates. The conversion of β-ketoesters to chiral enamines is followed by reaction with in situ generated strained arynes or cyclic alkynes. Hydrolytic workup provides the arylated or alkenylated products in enantiomeric excesses as high as 96%. We also describe the one-pot conversion
我们报告了一种使用β-酮酯衍生底物从芳烃和相关应变中间体的反应合成立体定义的四元中心的简便方法。β-酮酯转化为手性烯胺,然后与原位生成的应变芳炔或环炔反应。水解后处理可提供对映体过量高达 96% 的芳基化或烯基化产物。我们还描述了 β-酮酯底物一锅法转化为相应的对映体富集的 α-芳基化产物。计算显示了手性如何从 N 结合手性助剂转移到最终产品。这是手性亲核试剂捕获芳炔以设置新立体中心的首次理论研究。我们的方法为立体选择性β-酮酯芳基化/烯基化这一具有挑战性的问题提供了解决方案,并形成了四元中心。
Chiral N-heterocyclic carbenes as asymmetric acylation catalysts
作者:Yumiko Suzuki、Kazuyuki Muramatsu、Kaori Yamauchi、Yasuko Morie、Masayuki Sato
DOI:10.1016/j.tet.2005.09.071
日期:2006.1
N-heterocyclic carbenes are generated from C2-symmetric 1,3-bis(1-arylethyl)imidazolium salts and potassium tert-butoxide. These C2-symmetric imidazolidenyl carbenes catalyzeenantioselectiveacylation of racemicsecondaryalcohols. The asymmetric acylation of 1-(1-naphthyl)ethanol was achieved in up to 68% ee of the acylated product, using (R,R)-1,3-bis[(1-naphthyl)ethyl]imidazolium tetrafluoroborate as a precursor
EFFICIENT RESOLUTION OF (±)-1-(9-ANTHRYL)ETHYLAMINE
作者:Marin Roje、Zdenko Hameršak、Vitomir Šunjić
DOI:10.1081/scc-120014769
日期:2002.1
for efficient resolution of (±)-1-(9-anthryl)ethylamine ((±)-1) by fractional crystallization of its salts with (S)-(+)-mandelic acid (2) are reported. When crystallization was performed by fast addition of chloroform solution of an equivalent of (±)-1 to the hot chloroform solution of (+)-2, crystals of mandelate of (+)-1-(9-anthryl)ethylamine ((R,S)-3) are collected in 56% yield. (R)-(+)-1 (98.6% e
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