scholarly journals Asymmetric Henry Reaction of Nitromethane with Substituted Aldehydes Catalyzed by Novel In Situ Generated Chiral Bis(β-Amino Alcohol-Cu(OAc)2·H2O Complex

Catalysts ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1208
Author(s):  
Abdullah Saleh Alammari ◽  
Abdullah Mohammed Al-Majid ◽  
Assem Barakat ◽  
Saeed Alshahrani ◽  
Mohammad Ali ◽  
...  
Keyword(s):  
Amino Alcohol ◽  
Aromatic Aldehydes ◽  
Catalyst System ◽  
Green Solvent ◽  
Henry Reaction ◽  
Key Factors ◽  
Reaction Conditions ◽  
Catalyst Complex ◽  
High Yields

Novel chiral thiophene-2,5-bis(β-amino alcohol) ligands (L1–L5) were designed and synthesized from thiophene-2,5-dicarbaldehyde (3) with chiral β-amino alcohols (4a–e) in 4 steps with overall 23% yields. An in situ generated L-Cu(OAc)2·H2O catalyst system was found to be highly capable catalyst for the asymmetric Henry reaction of nitromethane (7) with various substituted aromatic aldehydes (6a–m) producing chiral nitroaldols product (8a–m) with excellent enantiomeric purity (up to 94.6% ee) and up to >99% chemical yields. 20 mol% of L4-Cu(OAc)2 catalyst complex in EtOH was effective for the asymmetric Henry transformation in 24 h, at ambient temperature. Ease of ligand synthesis, use of green solvent, base free reaction, mild reaction conditions, high yields and excellent enantioselectivity are all key factors that make this catalytic system robust and highly desirable for the access of versatile building block β-nitro alcohol in practical catalytic usage via asymmetric Henry reaction.

The Immobilized Copper on Nickel Ferrite: A Magnetically Superior Nanocatalyst for Chemoselective and Knoevenagel Synthesis of Bisdimedones and 1,8-Dioxo-octahydroxanthenes under Solvent-Free Conditions

2019 ◽  
Vol 16 (6) ◽  
pp. 939-947 ◽  
Author(s):  
Behzad Zeynizadeh ◽  
Soleiman Rahmani ◽  
Arezu Hallaj
Keyword(s):  
Catalytic Activity ◽  
Aromatic Aldehydes ◽  
Catalyst System ◽  
Solvent Free ◽  
Biologically Active ◽  
Knoevenagel Reaction ◽  
Reaction Conditions ◽  
Step Procedure ◽  
Solvent Free Conditions ◽  
High Yields

Aim and Objective: Nowadays, bisdimedones and 1,8-dioxo-octahydroxanthenes are considered as biologically active materials. Due to this, the synthesis of the mentioned materials is the subject of more interest. Although most of the reported methods have their own merits, however, they generally require the use of expensive reagents, hazardous organic solvents, a tedious workup procedure and reduced recyclability of the applied catalyst system. Overcoming of the above mentioned drawbacks, therefore, encouraged us to investigate the capability of nanostructured NiFe2O4@Cu towards the synthesis of bisdimedones and 1,8- dioxo-octahydroxanthenes under green reaction conditions. Materials and Methods: Nanoparticles of NiFe2O4@Cu were prepared via a two-step procedure including the preparation of NiFe2O4 by solid-state grinding of Ni(OAc)2·4H2O and Fe(NO3)3·9H2O in the presence of NaOH followed by the immobilization of Cu(0) on the surface of NiFe2O4 nucleus via hydrazine hydrate reduction of Cu(NO3)2·3H2O. Results: After the synthesis of NiFe2O4@Cu, the catalytic activity of the Cu-nanocatalyst towards Knoevenagel reaction of aromatic aldehydes with dimedone under different reaction conditions was investigated. The examinations showed that using the molar equivalents of aromatic aldehydes (1 mmol) and dimedone (2 mmol) in the presence of 0.15 g NiFe2O4@Cu under solvent-free conditions chemoselectively afforded structurally different bisdimedone products at 60°C and 1,8-dioxo-octahydroxanthenes at 120°C. Conclusion: In this study, magnetically, nanoparticles of NiFe2O4@Cu were prepared and then characterized using different analyses. The catalytic activity of the prepared Cu-nanocatalyst was also studied towards solvent-free Knoevenagel condensation of aromatic aldehydes with dimedone. All the reactions were carried out within 15-240 min to afford bisdimedone and 1,8-dioxo-octahydroxanthene products in high yields.

scholarly journals The first in situ synthesis of 1,3-dioxan-5-one derivatives and their direct use in Claisen-Schmidt reactions

2019 ◽  
Vol 25 (1) ◽  
pp. 85-90 ◽  
Author(s):  
M. Javad Poursharifi ◽  
Mohammad M. Mojtahedi ◽  
M. Saeed Abaee ◽  
Mohammad M. Hashemi
Keyword(s):  
Acetic Acid ◽  
Aromatic Aldehydes ◽  
In Situ Synthesis ◽  
Stepwise Procedures ◽  
Time Periods ◽  
High Yields ◽  
Short Time ◽  
Direct Use ◽  
Derivatives Of

AbstractA method is developed for in situ generation of 1,3-dioxan-5-one derivatives 2. These compounds are simple precursors for accessing carbohydrate structures and previously had to be produced via stepwise procedures using excessive amounts of reagents. In the present work, three different derivatives of 2 were synthesized via the reaction of trialkoxyalkanes with dihydroxyacetone dimer 1 in the presence of acetic acid as the catalyst. In the same pot, derivatives of 2 were reacted with aromatic aldehydes and 30 mol% of pyrrolidine to obtain high yields of the respective bischalcones 3 within short time periods.

scholarly journals A Solvent-Free Protocol for the Green Synthesis of 5-Arylidene-2,4-thiazolidinediones Using Ethylenediamine Diacetate as Catalyst

2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
Yuliang Zhang ◽  
Zhongqiang Zhou
Keyword(s):  
Knoevenagel Condensation ◽  
Aromatic Aldehydes ◽  
Solvent Free ◽  
Reusable Catalyst ◽  
Efficient Synthesis ◽  
Reaction Conditions ◽  
Solvent Free Conditions ◽  
High Yields ◽  
Work Up ◽  
Solvent Free Reaction

A simple and efficient synthesis of 5-arylidene-2,4-thiazolidinediones by the Knoevenagel condensation of aromatic aldehydes with 2,4-thiazolidinedione catalyzed by ethylenediamine diacetate under solvent-free conditions is described. The major advantages of this method are simple experimental and work-up procedures, solvent-free reaction conditions, small amount of catalyst, short reaction time, high yields, and utilization of an inexpensive and reusable catalyst.

A Green Approach for the Synthesis of Novel 7,11-Dihydro-6H-chromeno[3,4-e]isoxazolo[5,4-b]pyridin-6-one Derivatives Using Acidic Ionic Liquid [C4mim][HSO4]

2016 ◽  
Vol 69 (9) ◽  
pp. 1049 ◽  
Author(s):  
Sudesh Kumari ◽  
M. Rajeswari ◽  
Jitender M. Khurana
Keyword(s):  
Ionic Liquid ◽  
Crystal Packing ◽  
Aromatic Aldehydes ◽  
Green Solvent ◽  
One Pot ◽  
X Ray ◽  
Acidic Ionic Liquid ◽  
Green Approach ◽  
Wide Range ◽  
High Yields

A multicomponent reaction capable of affording a wide range of novel 7,11-dihydro-6H-chromeno[3,4-e]isoxazolo[5,4-b]pyridin-6-one derivatives via one-pot three-component condensation of 4-hydroxycoumarin, aromatic aldehydes, and 5-amino-3-methylisoxazole in ionic liquid 1-butyl-3-methylimidazolium hydrogen sulfate ([C4mim][HSO4]) is reported. Structures have been confirmed by spectral and X-ray studies. Crystal packing of 4b has also been reported. Green solvent, short reaction time, easy workup, and high yields are the salient features of the present protocol.

One Pot Three Component Synthesis of 9-arylpolyhydroacridine Derivatives in an Ionic Liquid Medium

2005 ◽  
Vol 2005 (9) ◽  
pp. 600-602 ◽  
Author(s):  
Yu-Ling Li ◽  
Mei-Mei Zhang ◽  
Xiang-Shan Wang ◽  
Da-Qing Shi ◽  
Shu-Jiang Tu ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Ionic Liquids ◽  
Ammonium Acetate ◽  
Aromatic Aldehydes ◽  
Environmentally Benign ◽  
Reaction Conditions ◽  
One Pot ◽  
High Yields ◽  
Work Up ◽  
Ionic Liquid Medium

In this paper the preparation of 3,3,6,6-tetramethyl-9-aryl-1,2,3,4,5,6,7,8,9,10- decahydroacridin-1,8-dione derivatives from aromatic aldehydes, 5,5-dimethyl-1,3- cyclohexanedione and ammonium acetate in ionic liquids [bmim+][BF4-] is described. This new method has the advantages of easier work-up, milder reaction conditions, high yields and an environmentally benign procedure compared with other methods.

scholarly journals One-Step Synthesis of Acylboron Compounds via Cu-Catalyzed Carbonylative Borylation of Alkyl Halides

2020 ◽  
Author(s):  
Cheng Li-Jie ◽  
Zhao Siling ◽  
Neal Mankad
Keyword(s):  
Alkyl Halides ◽  
Efficient Synthesis ◽  
Mechanistic Studies ◽  
Acyl Halide ◽  
Reaction Conditions ◽  
One Pot ◽  
One Step ◽  
High Yields ◽  
Tertiary Alkyl

A Cu-catalyzed carbonylative borylation of unactivated alkyl halides has been developed, enabling efficient synthesis of aliphatic potassium acyltrifluoroborates (KATs) in high yields by treating the in-situ formed tetracoordinated acylboron intermediates with aqueous KHF2. A variety of functional groups are tolerated under the mild reaction conditions, and primary, secondary and tertiary alkyl halides are all applicable. In addition, this method also provides facile access to N-methyliminodiacetyl (MIDA) acylboronates as well as α-methylated potassium acyltrifluoroborates in a one-pot manner. Mechanistic studies indicate a radical atom transfer carbonylation (ATC) mechanism to form acyl halide intermediates that are subsequently borylated by (NHC)CuBpin.<br>

Highly Enantioselective Michael Addition of Cyclic Diketones to β,γ-Unsaturated α-Keto Esters Catalyzed by Squaramide Organocatalyst

Synthesis ◽  
2022 ◽  
Author(s):  
Zhi-Wei Ma ◽  
Chuan-Chuan Wang ◽  
Quan-Jian Lv ◽  
Xiao-Pei Chen ◽  
Ai-Qin Li ◽  
...  
Keyword(s):  
Michael Addition ◽  
Large Scale ◽  
Catalyst System ◽  
Catalyst Loading ◽  
Reaction Conditions ◽  
Keto Esters ◽  
Bicyclic Compounds ◽  
Asymmetric Michael Addition ◽  
High Yields ◽  
Low Catalyst Loading

AbstractA new tertiary amine-squaramide organocatalyst has been developed and applied to the asymmetric Michael addition of cyclic diketones to β,γ-unsaturated α-keto esters. The catalyst system performed well with a low catalyst loading of 1 mol% under mild reaction conditions. A series of synthetically and pharmaceutically useful chiral bicyclic compounds were obtained in high yields (up to 97%) with excellent enantioselectivities (up to 99 % ee). Furthermore, this catalytic system can be used efficiently in large-scale reactions with the yields and enantioselectivities being maintained.

scholarly journals A Simple and Green Procedure for the Synthesis of 5-Arylidenerhodanines Catalyzed by Diammonium Hydrogen Phosphate in Water

2013 ◽  
Vol 2013 ◽  
pp. 1-4
Author(s):  
Liangliang Han ◽  
Tao Wu ◽  
Zhongqiang Zhou
Keyword(s):  
Reaction Times ◽  
Aromatic Aldehydes ◽  
Hydrogen Phosphate ◽  
Reaction Conditions ◽  
Efficient Procedure ◽  
Diammonium Hydrogen Phosphate ◽  
High Yields ◽  
Green Procedure ◽  
Work Up ◽  
Diammonium Hydrogen

A simple and efficient procedure for the synthesis of 5-arylidenerhodanines by condensation of aromatic aldehydes with rhodanine in water using diammonium hydrogen phosphate as catalyst is described. The procedure offers several advantages including environmentally friendly, mild reaction conditions, short reaction times, high yields, and simple experimental and work-up procedures.

scholarly journals Gold(I)-catalyzed intramolecular cyclization/intermolecular cycloaddition cascade as a fast track to polycarbocycles and mechanistic insights

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Cheng Zhang ◽  
Kemiao Hong ◽  
Chao Pei ◽  
Su Zhou ◽  
Wenhao Hu ◽  
...  
Keyword(s):  
Fast Track ◽  
Cycloaddition Reaction ◽  
Structural Diversity ◽  
Mechanistic Studies ◽  
Reaction Conditions ◽  
In Situ Formation ◽  
Increasing Demand ◽  
High Yields ◽  
Synthetic Intermediate

AbstractMetal carbene is an active synthetic intermediate, which has shown versatile applications in synthetic chemistry. Although a variety of catalytic methods have been disclosed for the generation of carbene species from different precursors, there is an increasing demand for the development of efficient and practical approaches for the in-situ formation of metal carbene intermediates with structural diversity and unrevealed reactivity. Herein we report a gold-catalyzed cascade protocol for the assembly of polycarbocyclic frameworks in high yields under mild reaction conditions. Mechanistic studies indicate that the unique β-aryl gold-carbene species, generated via gold-promoted 6-endo-dig diazo-yne cyclization, is the key intermediate in this reaction, followed by a [4 + 2]-cycloaddition with external alkenes. In comparison to the well-documented metal carbene cycloadditions, this carbene intermediate serves as a 4-C synthon in a cycloaddition reaction. A variety of elusive π-conjugated polycyclic hydrocarbons (CPHs) with multiple substituents are readily accessible from the initially generated products by a mild oxidation procedure.

In situ Generation and Utilization of CO: An Efficient Route towards N-Substituted Saccharin via Carbonylative Cyclization of 2-Iodosulfonamides

Synlett ◽  
2017 ◽  
Vol 28 (15) ◽  
pp. 2000-2003 ◽  
Author(s):  
Bhalchandra Bhanage ◽  
Sujit Chavan ◽  
Adithyaraj K.
Keyword(s):  
Catalyst System ◽  
Reaction Conditions ◽  
Efficient Route ◽  
In Situ Generation

The present protocol demonstrates the synthesis of N-substituted saccharines via carbonylative cyclization of 2-iodosulfonamides using a Pd(OAc)2/Xantphos catalyst system and phenyl formate as a CO source. A variety of saccharin derivatives is synthesized under milder reaction conditions.

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