Novel Synthesis, Molecular Structure, and Theoretical Studies of Dispiro Compounds via Pseudo-eight-component Reaction

We have developed a diastereoselective synthesis of dispiro compounds through a one-pot domino pseudo-eight-component reaction of amines, aldehydes, and Meldrum’s acid. This method resulted in the generation of complex products with four stereocentres and involves formation of 10 new bonds. Quantum mechanical calculations were undertaken in order to determine the stability of the eight diastereomer structures of compound 4a. The crystal structure of 4k was determined by X-ray crystallography. Reaction mechanism can proceed through Knoevenagel, Aldol condensations, Diels-Alder cycloaddition, and Michael addition.

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Uncatalyzed diastereoselective synthesis of alkyliminofurochromone-derived benzylmalononitriles via a three-component cascade reaction: competition between Diels–Alder cycloaddition and Michael addition

Organic & Biomolecular Chemistry ◽

10.1039/d0ob02540b ◽

2021 ◽

Author(s):

Mohammad Bagher Teimouri ◽

Zahra Mokhtare ◽

Hamid Reza Khavasi

Keyword(s):

Michael Addition ◽

Heterocyclic Ring ◽

Cascade Reaction ◽

Diels Alder ◽

Chemical Bonds ◽

Diastereoselective Synthesis ◽

Atom Economy ◽

One Pot

Three new chemical bonds and three stereogenic centres and one heterocyclic ring were assembled stereoselectively in a convenient high atom-economy one-pot operation.

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A new one-pot three-component synthesis of 4-aryl-6-cycloamino-1,3,5-triazin-2-amines under microwave irradiation

Synthesis ◽

10.1055/a-1401-2795 ◽

2021 ◽

Author(s):

Muhammad Syafiq Bin Shahari ◽

Ahmad Junaid ◽

Edward R. T. Tiekink ◽

Anton V. Dolzhenko

Keyword(s):

Microwave Irradiation ◽

Aromatic Aldehydes ◽

Antileukemic Activity ◽

One Pot ◽

Biological Screening ◽

X Ray ◽

X Ray Crystallography ◽

Cyclic Amines ◽

Three Component Reaction ◽

Fast Synthesis

A new method for the fast synthesis of diverse 4-aryl-6-cycloamino-1,3,5-triazin-2-amines was developed. The synthesis is performed under microwave irradiation in a one-pot manner from cyanoguanidine, aromatic aldehydes, and cyclic amines. Their three-component reaction in the presence of hydrochloric acid produced dihydrotriazines, which were then converted (without isolation) to the targeted compounds via aromatic dehydrogenation in the presence of alkali. The reaction tolerated various aromatic aldehydes (including heterocyclic) and cyclic amines. Crystal structures of two representative 4-aryl-6-morpholino-1,3,5-triazin-2-amines were established by X-ray crystallography. The results of preliminary biological screening identified potent antileukemic activity for 6-(3,4-dihydroisoquinolin-2(1<i>H</i>)-yl)-4-phenyl-1,3,5-triazin-2-amine.

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Zirconium complexes of a cyclopentadienyl-amido ligand with a pendant amine donor via amine and alkane elimination

Canadian Journal of Chemistry ◽

10.1139/v96-186 ◽

1996 ◽

Vol 74 (9) ◽

pp. 1696-1703 ◽

Cited By ~ 10

Author(s):

Ying Mu ◽

Warren E. Piers ◽

Donald C. MacQuarrie ◽

Michael J. Zaworotko

Keyword(s):

Lewis Acids ◽

Methyl Chloride ◽

Monoclinic Space Group ◽

One Pot ◽

Amido Complexes ◽

X Ray ◽

X Ray Crystallography ◽

Zirconium Complexes ◽

Alkane Elimination

Zirconium complexes of the multidentate ligand CpHNMeSiN(H)R (SiNR = -SiMe2N-t-butyl; NMe = -CH2CH2NMe2, 1) were prepared and characterized via amine and alkane elimination procedures. Reaction of 1 with Zr(NMe2)4 gave a mixture of bis-amido complexes 2 in which the ligand was 1,2 and 1,3 substituted. This mixture was converted to the analogous dichlorides 3 using Me2NH•HCl and 1,3-3 was purified at this stage; alternatively, 1,3-3 was obtained in one pot from 1 and Zr(NMe2)4 in ≈70% yield. Conversion of 1,3-3 to dimethyl compound (CpNMeSiNR)Zr(CH3)2, 1,3-4, was accomplished via reaction of the dichloride with methyllithium; methide abstraction with the Lewis acids B(C6F5)3 and [Ph3C]+[B(C6F5)4]− generated the cationic alkyls [(CpNMeSiNR)Zr(CH3)]+[R′B(C6F5)3]− (R′ = CH3, 6a; C6F6, 6b), which were characterized by NMR spectroscopy. Zirconium complexes containing 1 ligated as its 1,2 isomer were obtained from alkane elimination reactions between 1 and in situ prepared RnZrCl4−n (R = CH3, n = 3; R = CH2SiMe3, n = 2). 1,2-3 and the methyl chloride complex 1,2-(CpNMeSiNR)Zr(CH3)Cl, 5, were obtained in 18 and 30% yield, respectively. Complex 5 was characterized by X-ray crystallography (monoclinic, space group P21/a, a = 9.6951(10) Å, b = 14.3794(16) Å, c = 14.364(3) Å, V = 1990.3(5) Å3, Z = 4, R = 0.046, Rw = 0.041.) Key words: amine elimination, Cp-amido, zirconium complexes.

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Silane catecholates: versatile tools for self-assembled dynamic covalent bond chemistry

Chemical Communications ◽

10.1039/c9cc02103e ◽

2019 ◽

Vol 55 (43) ◽

pp. 6066-6069 ◽

Cited By ~ 8

Author(s):

Yoshiteru Kawakami ◽

Tsuyoshi Ogishima ◽

Tomoki Kawara ◽

Shota Yamauchi ◽

Kazuhiko Okamoto ◽

...

Keyword(s):

Covalent Bond ◽

One Pot ◽

X Ray ◽

X Ray Crystallography ◽

Self Assembled

Shape-persistent macrocycles and 3D nanocages have been prepared in one-pot under MeCN-promoted dynamic covalent bond conditions starting from silane catecholates, whose structures were confirmed by X-ray crystallography.

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Novel synthesis of furancarboxylate derivatives via cyclization reactions of (E)-ethyl 3-aryl-2-cyanoacrylates and ethyl glycinate hydrochloride

Journal of Chemical Research ◽

10.1177/1747519820959597 ◽

2020 ◽

pp. 174751982095959

Author(s):

Naili Luo ◽

Shan Wang ◽

Zhenjie Su ◽

Cunde Wang

Keyword(s):

Synthetic Approach ◽

Cyclization Reactions ◽

X Ray ◽

X Ray Crystallography ◽

Mild Conditions ◽

Novel Synthesis ◽

Substituted Furans

An efficient synthetic approach for the preparation of densely substituted furans starting from ( E)-ethyl 3-aryl-2-cyanoacrylates and ethyl glycinate hydrochloride mediated by 1,8-diazabicyclo[5.4.0]undec-7-ene in the presence of water is investigated. The reactions are carried out under mild conditions in N,N-dimethylformamide at 95 °C. The products are cleanly obtained in 50%–57% yields, resulting in an appealing alternative for accessing polysubstituted furan-2,4-dicarboxylates. The structure of a typical product, diethyl 5-amino-3-( p-tolyl)furan-2,4-dicarboxylate, is confirmed by X-ray crystallography.

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Using Molecular Dynamics Simulations to Compare the Stability of Lysenin Structures Obtained through X-ray Crystallography and Single-Particle Cryo-Electron Microscopy

Biophysical Journal ◽

10.1016/j.bpj.2017.11.1883 ◽

2018 ◽

Vol 114 (3) ◽

pp. 337a

Author(s):

Vivek Govind Kumar

Keyword(s):

Electron Microscopy ◽

Molecular Dynamics ◽

Molecular Dynamics Simulations ◽

Single Particle ◽

X Ray ◽

X Ray Crystallography ◽

Cryo Electron Microscopy ◽

The Stability ◽

Dynamics Simulations

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One-pot synthesis of 5-(8-ethoxycarbonyl-1-naphthyl)-10,15,20-triphenyl porphyrin (ENTPP) and spontaneous resolution upon crystallization

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424611003136 ◽

2011 ◽

Vol 15 (03) ◽

pp. 197-201 ◽

Cited By ~ 12

Author(s):

Juanxia Yang ◽

Jiaxun Jiang ◽

Weiguang Fang ◽

Xiaoxu Kai ◽

Chuanjiang Hu ◽

...

Keyword(s):

Soret Band ◽

Ester Group ◽

Spontaneous Resolution ◽

Cd Spectra ◽

One Pot ◽

Nmr Spectrum ◽

X Ray ◽

X Ray Crystallography ◽

H Nmr ◽

Entire Structure

5-(8-ethoxycarbonyl-1-naphthyl)-10,15,20-triphenyl porphyrin (ENTPP) has been synthesized in a one-pot reaction, and the corresponding chiral crystalline samples have been obtained by spontaneous resolution. 1 H NMR spectrum suggests it is mononaphthyl substituted species and an ethyl group is over the porphyrin plane. The structure has been further confirmed by X-ray crystallography. ENTPP·C6H14 (C57H50N4O2 ): monoclinic, P21, a = 10.707(2) Å, b = 12.203(2) Å, c = 17.858(4) Å, β = 103.06(3)°, V = 2272.8(8) Å3, Z = 2. The 8-position substituent, ester group, lies above the porphyrin plane and leads to the conformational chirality. The entire structure is built up with homochiral molecules, which leads to a chiral crystal through packing in P21 space group. Circular dichroism (CD) spectra have exhibited remarkable absorptions in the Soret band region, which further confirms the homochirality of the crystalline samples.

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