Zinc(II) Perchlorate Hexahydrate Catalyzed Opening of Epoxide Ring by Amines: Applications to Synthesis of (<i>RS</i>)/(<i>R</i>)-Propranolols and (<i>RS</i>)/(<i>R</i>)/(<i>S</i>)-Naftopidils
作者:Shivani、Brahmam Pujala、Asit K. Chakraborti
DOI:10.1021/jo062674j
日期:2007.5.1
perchlorate hexahydrate was found to be the best catalyst compared to other metal perchlorates. The counteranion modulated the catalytic property of the various Zn(II) compounds that followed the order Zn(ClO4)2·6H2O ≫ Zn(BF4)2 ∼ Zn(OTf)2 ≫ ZnI2 > ZnBr2 > ZnCl2 > Zn(OAc)2 > Zn(CO3)2 in parallelism with the acidic strength of the corresponding protic acids (except for TfOH). The applicability of the methodology
X‐ray structurally characterized Mo (VI), Fe (III) and Cu (II) complexes of amide‐imine conjugate: (bio)catalytic and histidine recognition studies
作者:Sabyasachi Ta、Milan Ghosh、Noor Salam、Jayanta Das、Manirul Islam、Paula Brandão、Vítor Félix、Jesus Sanmartin、Debasis Das
DOI:10.1002/aoc.5823
日期:2020.10
nzohydrazide (H2LPTASAL), derived from 4‐methyl‐benzoicacid hydrazide (PTA) and 2‐hydroxybenzaldehyde is used to prepare Mo (VI), Cu (II) and Fe (III) complexes. The X‐ray structurally characterized complexes have been explored as catalyst for amine assisted asymmetric ring opening (ARO) of epoxide, carbon‐heteroatom cross‐coupling and ethyl benzene oxidation. In addition, their catecholase like activities
衍生自4-甲基苯甲酸酰肼(PTA)和2的酰胺-亚胺共轭物(E)-N'-((2-羟基苯甲酰基-1-基)亚甲基)-4-甲基苯甲酰肼(H 2 L PTASAL) ‐羟基苯甲醛用于制备Mo(VI),Cu(II)和Fe(III)配合物。X射线的结构表征的配合物已被用作催化剂,用于胺辅助的环氧不对称开环(ARO),碳杂原子交叉偶联和乙苯氧化。另外,已经充分研究了它们的儿茶酚酶样活性。而且,Cu(II)配合物通过荧光光谱法选择性地识别组氨酸。
Glycerine and CeCl3˙7H2O: An Efficient and Recyclable Reaction Medium for Ring Opening of Epoxides with Thioamides and Amines
作者:A. Narsaiah、Sachin Wadavrao、A. Reddy、J. Yadav
DOI:10.1055/s-0030-1258366
日期:2011.2
Oxiranes undergo rapid ring-opening reaction with a range of thioamides and amines to afford the corresponding β-amino alcohol derivatives. The reactions were carried out using glycerine and cerium(III) chloride as a recyclable reaction medium. All the reactions were carried out at room temperature and the products were obtained in excellent yields.
Zinc Tetrafluoroborate Hydrate as a Mild Catalyst for Epoxide Ring Opening with Amines: Scope and Limitations of Metal Tetrafluoroborates and Applications in the Synthesis of Antihypertensive Drugs (<i>RS</i>)/(<i>R</i>)/(<i>S</i>)-Metoprolols
作者:Brahmam Pujala、Shivani Rana、Asit K. Chakraborti
DOI:10.1021/jo201473f
日期:2011.11.4
reaction at the benzylic carbon of the epoxide ring. A reversal of regioselectivity (91:1–69:31) in favor of the reaction at the terminal carbon of the epoxide ring was observed for reaction with morpholine. The regioselectivity was dependent on the electronic and steric factors of the epoxide and the pKa of the amine and independent of amine nucleophilicity. The role of the metal tetrafluoroborates is
已经研究了金属四氟硼酸盐与胺进行环氧化物开环反应的范围和局限性,并且发现Zn(BF 4)2 · x H 2 O是一种温和而有效的催化剂,在无溶剂条件下于200 ℃提供高收率。 rt具有出色的化学,区域和立体选择性。催化效率依次为Zn(BF 4)2 · x H 2 O≫ Cu(BF 4)2 · x H 2 O> Co(BF 4)2 ·6H 2 O≫ Fe(BF 4)2 ·6H2 O> LiBF 4与环己烯氧化物和Zn(BF 4)2 · x H 2 O≫ Co(BF 4)2 ·6H 2 O≫ Fe(BF 4)2 ·6H 2 O> Cu(BF 4)反应2 · x H 2 O,用于氧化二苯乙烯,但AgBF 4是无效的。对于苯乙烯氧化物与苯胺的反应,四氟硼酸金属具有相当的区域选择性(1:99–7:93),并且在环的苄基碳上具有优先反应。与吗啉反应时,观察到区域选择性的逆转(91:1–69:31),有
The Selective C-3 Opening of Aromatic 2,3-Epoxy Alcohols/Epoxides with Aromatic Amines Catalysed by β-Cyclodextrin in Water
A simple and mild procedure has been developed for the first time for the C-3selective ring-opening of aromatic 2,3-epoxy alcohols/epoxides with aromatic amines catalysed by (3-cyclodextrin in water at room temperature to afford the corresponding β-aminoalcohols in excellent yields with high regioselectivity.