Establishing Supramolecular Control over Solid-State Architectures: A Simple Mix and Match Strategy
摘要:
With the help of robust principles of crystal engineering, it is possible to construct co-crystals where two or more different molecular entities coexist in the same crystalline lattice; the supramolecular assembly is driven by noncovalent interactions, most commonly by hydrogen bonds. We have synthesized two ditopic amide based ligands (N-(4-pyridin-2-yl)-isonicotinamide) and (N-(3-pyridin-2-yl)nicotinamide) and systematically established their binding preferences when faced with aliphatic dicarboxylic acids with an odd and even number of carbon atoms. Each ligand was co-crystallized with four odd and four even-chain dicarboxylic acids, and 13/16 reactions produced crystals suitable for single-crystal structure determination. On the basis of these results, it is dear that carefully selected systems can be manipulated to produce assemblies in the solid state with very precise control over topology and dimensionality. These ligands can be made to produce either 0-D or 1-D architectures simply by fine-tuning the choice of co-crystallizing agent in the supramolecular synthesis. This mix-and-match strategy allows us to mimic the reliability and versatility of covalent synthesis, in terms of successfully preparing a target with predetermined connectivity and metrics.
A Cross-Coupling Approach to Amide Bond Formation from Esters
作者:Taoufik Ben Halima、Jaya Kishore Vandavasi、Mohanad Shkoor、Stephen G. Newman
DOI:10.1021/acscatal.7b00245
日期:2017.3.3
A palladium-catalyzed cross-coupling between aryl esters and anilines is reported, enabling access to diverse amides. The reaction takes place via activation of the C–O bond by oxidative addition with a Pd–NHC complex, which enables the use of relatively non-nucleophilic anilines that otherwise require stoichiometric activation with strong bases in order to react. High yields of aromatic, aliphatic
Mapping out the Relative Influence of Hydrogen and Halogen Bonds in Crystal Structures of a Family of Amide-Substituted Pyridines
作者:Amila M. Abeysekera、Victor W. Day、Abhijeet S. Sinha、Christer B. Aakeröy
DOI:10.1021/acs.cgd.0c01086
日期:2020.11.4
Bz-I and 2Pyr-I, the primary hydrogenbonding resembled that of the other members of the family, indicating that the interactions mediated via the iodine atom were complementary to rather than competitive with the hydrogen bonds. Two polymorphs of 4Pyr-I were found, and in both forms, a halogenbond was formed with the N(py) acceptor which was engaged in N–H···N hydrogen bonds in the other members of
Structural diversity, spectral characterization and computational studies of Cu(I) complexes with pyridylamide ligands
作者:Ethan P. McMoran、Manuel N. Dominguez、Ethan M. Erwin、Douglas R. Powell、Gerard T. Rowe、Lei Yang
DOI:10.1016/j.ica.2016.03.011
日期:2016.5
) (2) and [Cu(4-ppa)(NCCH3)2]BF4 (5) displayed mononuclear structures with tetrahedral geometries on Cu(I) centers. Dinuclear complex [Cu2(2-pina)3(NCCH3)4](SbF6)2 (3) and tetranuclearcluster [Cu4(2-pina)4(NCCH3)4](SbF6)4 (4) were afforded from the same reaction in CH3CN and DMF, respectively. Detailed analysis of X-ray crystal structures and Hirshfeld surface maps suggested that the weak non-covalent
Iodine-Promoted N-Acylation of Amines with Hydrazide: An Efficient Metal-Free Amidation
作者:Keyume Ablajan、Long Tian、Qianwei Zhang
DOI:10.1055/a-1838-9491
日期:2022.10
protocol for the amidation of hydrazide with amine has been developed by utilizing I2 as an oxidant under metal- and base-free conditions at room temperature. N-Acylation products of amines were obtained in good to excellent yields without using toxic reagents. This method is operationally straightforward and tolerates aliphatic/aromatic and primary/secondaryamines with different hydrazides.
通过在室温下在无金属和无碱条件下使用 I 2作为氧化剂,开发了一种用于酰肼与胺的酰胺化的有效方案。在不使用有毒试剂的情况下,以良好至极好的收率获得了胺的 N-酰化产物。该方法操作简单,可耐受脂肪族/芳香族和伯/仲胺与不同的酰肼。
Synthesis and characterization of divalent metal complexes with bipyridylamide ligands
作者:Ethan P. McMoran、Clement Mugenzi、Kyle Fournier、Mark Draganjac、Donavon Tony、Kwangkook Jeong、Douglas R. Powell、Lei Yang
DOI:10.1080/00958972.2015.1122188
日期:2016.2.1
Reaction of N-(4-pyridyl)picolinamide (4-ppa), N-(4-pyridyl)nicotinamide (4-pna), N-(4-pyridyl)isonicotinamide (4-pina), and N-(2-pyridyl)isonicotinamide (2-pina) with divalent metal salts led to the formation of six new coordination complexes. The X-ray structure of [Zn(4-ppa)(2)Cl-2] (1) shows a mononuclear structure with interesting intermolecular hydrogen bonding interactions. [Zn(4-pna)(OAc)(2)](n) (2), Cu(4-pna)(OTf)(2)(DMF)(2)](n) (3), [Zn(4-pina)(DMF)(4)](OTf)(2)}(n) (4), [Fe(4-pina)(DMF)(4)](OTf)(2)}(n) (5), and [Cu(2-pina)(OTf)(2)(DMF)(2)](n) (6) are one-dimensional coordination polymers with conformational differences caused by the coordination donor disposition, which demonstrates the flexibility of the pyridylamide ligands in polymeric structures. Reflectance UV-visible spectra and thermal properties of the coordination polymers are also reported.[GRAPHICS]