scholarly journals First example of an organocatalytic asymmetric Mannich reaction between aldimines of glycinates and sulphonyl imines

2016 ◽  
Vol 94 (9) ◽  
pp. 769-772 ◽  
Author(s):  
Lei Wu ◽  
Guangxun Li ◽  
Migu He ◽  
Yingwei Wang ◽  
Gang Zhao ◽  
...  
Keyword(s):  
Schiff Base ◽  
Schiff Bases ◽  
Mannich Reaction ◽  
High Yield ◽  
Metal Catalyst ◽  
Type Reaction

The catalytic enantioselective Mannich-type reaction between glycinate Schiff base and imines has been one of the most efficient routes for accessing α,β-diamino acids. However, the glycinate Schiff bases used in the references were almost ketimines. Only several examples of aldimines were used in the presence of metal catalyst. We developed the first example of an asymmetric direct Mannich reaction using aldimines of glycinates instead of ketimines of glycinates. The reaction was well catalyzed by chiral guanidine with high yield (up to 92%) and moderate stereoselectivity (up to 65%).

Synthesis of some new hydrazide-hydrazones related to isatin and its Mannich and Schiff bases

2016 ◽  
Vol 71 (11) ◽  
pp. 1147-1157 ◽  
Author(s):  
Elsayed M. Afsah ◽  
Saad S. Elmorsy ◽  
Soha M. Abdelmageed ◽  
Zaki E. Zaki
Keyword(s):  
Schiff Base ◽  
Schiff Bases ◽  
Mannich Reaction ◽  
Mannich Base ◽  
The Mannich Reaction

AbstractThe hydrazide-hydrazones 6a–d and 7a, b were obtained by treating isatin (1) or its Mannich base 2 with hydrazides incorporating piperidine, morpholine, and piperazine units. The reaction of 1 and 2 with hydrazides related to triazenes having piperidine, morpholine, and 1,2,3,4-tetrahydroisoquinoline moieties gave 12a–c and 13a–c. Treatment of 1 and 2 with iminodiacetohydrazide (14) and ethylenediamine tetraacetohydrazide (18) afforded 15–17 and 19a, b, respectively. The Mannich reaction of the Schiff base 20 with formaldehyde and the appropriate hydrazide or bis(hydrazide) gave 21a, b and 22a, b. The hydrazides related to Schiff bases 20 and 26 were used as precursors in synthesis of compounds incorporating two 2-oxoindoline units or formazan moiety.

Antimony(III) Chloride Catalyzed Direct Three Component One-pot Mannich Reaction

2009 ◽  
Vol 4 (2) ◽  
pp. 1934578X0900400
Author(s):  
Prashant Shukla ◽  
Nilmadhab Chattopadhyay ◽  
Sandip K. Nayak
Keyword(s):  
Ambient Temperature ◽  
Schiff Bases ◽  
Mannich Reaction ◽  
Aromatic Aldehydes ◽  
One Pot ◽  
Type Reaction ◽  
Reaction Proceeds ◽  
Acyclic Ketones

Antimony(III) chloride catalyzes the three component Mannich type reaction of a variety of in-situ generated Schiff bases generated from aromatic aldehydes and anilines with cyclic/acyclic ketones. The reaction proceeds smoothly at ambient temperature to afford the corresponding β-amino ketones in good yields with moderate to good diastereoselectivity.

scholarly journals Synthesis and Evaluation of Schiff Bases of 4-Amino-5-(chlorine substituted phenyl)-4H-1,2,4-triazole-3-thione as Antimicrobial Agents

2020 ◽  
Vol 41 (1) ◽  
pp. 26-35
Author(s):  
Kishor Devkota ◽  
Govinda Pathak ◽  
Bhushan Shakya
Keyword(s):  
Schiff Base ◽  
Schiff Bases ◽  
Antimicrobial Agents ◽  
Triazole Ring ◽  
Antimicrobial Activities ◽  
Biologically Active ◽  
Spectral Techniques ◽  
Schiff Base Derivatives ◽  
Bacteria And Fungi ◽  
Different Strains

Triazole ring system has attracted a continuously growing interest of synthetic organic chemists and those dealing with the medicinal compounds due to its versatile potential to interact with biological systems. Schiff bases are also considered as one of the most biologically active compounds.  The aim of the present study was to synthesize new Schiff bases bearing triazole nucleus and to assess their antimicrobial activities. Four new Schiff base derivatives of 1,2,4-triazole-3-thione were synthesized by combining two different pharmacophores viz. triazole nucleus and Schiff base moiety and were characterized by spectral techniques (UV, FT-IR, and NMR). The Schiff bases were evaluated for antibacterial (Staphylococcus aureus, Escherichia coli, and Klebsiella pneumoniae) and antifungal (Candida albicans) activities. The synthesized compounds exhibited good to moderate activities against different strains of bacteria and fungi tested.

Simple, efficient, high yield syntheses of substituted and unsubstituted 5-benzoylbarbituric acids, and their corresponding schiff base phenylhydrazones

2004 ◽  
Vol 41 (2) ◽  
pp. 233-246 ◽  
Author(s):  
Branko S. Jursic ◽  
Donna M. Neumann ◽  
Katharine L. Bowdy ◽  
Edwin D. Stevens
Keyword(s):  
Schiff Base ◽  
High Yield

Syntheses, Spectroscopy And Crystal Structures Of (R)-N-(1-Aryl-Ethyl)Salicylaldimines And [Rh{(R)-N-(1-Aryl-Ethyl)Salicylaldiminato}(η4-Cod)] Complexes

2007 ◽  
Vol 62 (6) ◽  
pp. 807-817 ◽  
Author(s):  
Mohammed Enamullah ◽  
A.K.M. Royhan Uddin ◽  
Anne-Christine Chamayou ◽  
Christoph Janiak
Keyword(s):  
Mass Spectrometry ◽  
Schiff Base ◽  
Schiff Bases ◽  
Structure Determination ◽  
Chelate Ring ◽  
Optical Rotation ◽  
X Ray ◽  
Mononuclear Complexes ◽  
Chiral Schiff Base ◽  
C Nmr

Condensation of salicylaldehyde with enantiopure (R)-(1-aryl-ethyl)amines yields the enantiopure Schiff bases (R)-N-(1-aryl-ethyl)salicylaldimine (HSB*; aryl = phenyl, 2-methoxyphenyl, 3- methoxyphenyl, 4-methoxyphenyl (4), 4-bromophenyl (5), 2-naphthyl). These Schiff bases readily react with dinuclear (acetato)(η4-cycloocta-1,5-diene)rhodium(I), [Rh(μ-O2CMe)(η4-cod)]2, to afford the mononuclear complexes, cyclooctadiene-((R)-N-(1-aryl-ethyl)salicylaldiminato-κ2N,O)- rhodium(I), [Rh(SB∗)(η4-cod)] (SB* = deprotonated chiral Schiff base = salicylaldiminate; aryl = phenyl (7), 2-methoxyphenyl, 4-methoxyphenyl, 4-bromophenyl, 2-naphthyl). The complexes have been characterized by IR, UV/vis, 1H/13C NMR and mass spectrometry, optical rotation as well as by single-crystal X-ray structure determination for 4, 5 and 7. The structure of 5 shows C-Br· · ·π contacts. Compound 7 is only the second example of a Rh(η4-cod) complex with a six-membered Rh-N,O-chelate ring

Notizen: Magnetic Studies on Schiff Base Complexes of Al(III) and Si(IV)

1974 ◽  
Vol 29 (7-8) ◽  
pp. 565-566 ◽  
Author(s):  
R. N. Prasad ◽  
J. P. Tandon
Keyword(s):  
Schiff Base ◽  
Schiff Bases ◽  
Schiff Base Complexes ◽  
Magnetic Studies ◽  
Magnetic Susceptibilities

The magnetic susceptibilities of some newly syntesized Al(III) and Si(IV) complexes of Schiff bases derived from the condensation of o-hydroxyacetophenone or 2-dydroxy-1-naphthaldehyde with hydroxyalkylamines or diamines have been measured and the data indicate their diamagnetic character.

Schiff Bases and Related Substances. III. Acetylation of a Schiff Base-Thiol Adduct1

1958 ◽  
Vol 80 (13) ◽  
pp. 3475-3478 ◽  
Author(s):  
Gardner W. Stacy ◽  
Richard I. Day ◽  
Richard J. Morath
Keyword(s):  
Schiff Base ◽  
Schiff Bases ◽  
Related Substances

Electronic Structure of Pseudotetrahedral Copper(II) Schiff Base Complexes

1977 ◽  
Vol 32 (5) ◽  
pp. 551-561 ◽  
Author(s):  
John R. Wasson ◽  
H. Wayne Richardson ◽  
William E. Hatfield
Keyword(s):  
Electronic Structure ◽  
Schiff Base ◽  
Schiff Bases ◽  
Opposite Direction ◽  
Hyperfine Coupling ◽  
Coupling Constants ◽  
Schiff Base Complexes ◽  
Hyperfine Coupling Constants ◽  
Structure Correlations

Copper(II) complexes with the Schiff bases formed by condensing t-butyl-, isopropyl-, cyclohexyl- and diphenylmethylamines with salicylaldehyde and 3-methoxy- and 5-nitrosalicyl-aldehyde have been prepared and characterized. The isotropic nuclear hyperfine coupling constants increase in the order t-butyl < isopropyl < cyclohexyl < diphenylmethyl for the N-substituents in the three series of complexes while isotropic g-values increased in the opposite direction. Spectra structure correlations were examined and discussed.

scholarly journals A novel approach toward the synthesis of some new tridentate Schiff bases from anil-like compounds

2016 ◽  
Vol 81 (10) ◽  
pp. 1111-1119 ◽  
Author(s):  
Fatemeh Bagheri ◽  
Abolfazl Olyaei
Keyword(s):  
Schiff Base ◽  
Formic Acid ◽  
Schiff Bases ◽  
Condensation Product ◽  
Reaction Times ◽  
Acid Catalyst ◽  
Schiff Base Ligands ◽  
Novel Approach ◽  
Solvent Free Conditions ◽  
Novel Method

A novel method was developed for synthesizing a series of new three dentate Schiff base ligands starting from hydroxynaphthalidene pyrimidinyl amines with o-phenylenediamines or o-aminophenol or 2-amino-3-hydroxy-pyri-dine in the presence of formic acid catalyst under solvent-free conditions. In these reactions [1+1] condensation product as half-unit ligand was obtained. Moreover, the reaction of hydroxynaphthalidene pyrimidinyl amines with 3,4-diamino-pyridine and 1,8-naphthalenediamine lead to the formation of C2-naphthylated imidazopyridine and dihydropyrimidine, respectively. The attractive features of this protocol are: use of inexpensive catalyst, operationally simple, short reaction times, easy handling, and good yields.

Phosphine-assisted C–H bond activation in Schiff bases and formation of novel organo cobalt complexes bearing Schiff base ligands

2018 ◽  
Vol 42 (6) ◽  
pp. 4646-4652 ◽  
Author(s):  
Hua Zhang ◽  
Junyang Xing ◽  
Yanhong Dong ◽  
Shangqing Xie ◽  
Shishuai Ren ◽  
...  
Keyword(s):  
Schiff Base ◽  
Schiff Bases ◽  
Bond Activation ◽  
Cobalt Complexes ◽  
Schiff Base Ligands

The sp2 C–H bond activation of the HCN moiety in diphenylphosphino benzalimines was realized using CoMe(PMe3)4 with the elimination of methane.

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