Versatile and Sustainable Synthesis of Cyclic Imides from Dicarboxylic Acids and Amines by Nb<sub>2</sub>O<sub>5</sub> as a Base‐Tolerant Heterogeneous Lewis Acid Catalyst

Ali, Muhammad; Siddiki, S. M. A. Hakim; Kon, Kenichi; Hasegawa, Jun‐ya; Shimizu, Ken‐ichi

doi:10.1002/chem.201404538

Cited by 35 publications

(41 citation statements)

References 62 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Inspired by recent reports that several metal oxides, such as Nb 2 O 5 , act as water‐tolerant Lewis acid catalysts, we recently reported that Nb 2 O 5 acts as a water‐tolerant Lewis acid catalyst for the direct imidation of dicarboxylic acids with amines and the direct amidation of esters with amines . We reported our preliminary results on the synthesis of cyclic imides from cyclic anhydrides, but detailed catalytic properties such as substrate scope and kinetic studies were not reported. Herein, we report a general catalytic method for the direct synthesis of cyclic imides from cyclic anhydrides with amines (or ammonia) under solvent‐free conditions.…”

Section: Catalyst Screening For the Synthesis Of Cyclic Imides From Amentioning

confidence: 99%

“…Nb 2 O 5 (surface area=54 m 2 g −1 ) was prepared by calcination of niobic acid (supplied by CBMM) at 500 °C for 3 h; the Lewis acid characteristics of Nb 2 O 5 are reported in our previous studies …”

Section: Catalyst Screening For the Synthesis Of Cyclic Imides From Amentioning

confidence: 99%

“…The reaction of succinic anhydride (10 mmol) with n ‐octylamine (10 mmol) in the presence of Nb 2 O 5 (50 mg) for 67 h gave the corresponding imide in 79 % yield. Previously, we reported the number of surface Lewis acid sites on the Nb 2 O 5 catalyst by pyridine adsorption IR spectroscopy at 200 °C . The turnover number (TON) with respect to the Lewis acid sites of Nb 2 O 5 (0.056 mmol g −1 ) was calculated to be 2820.…”

Section: Catalyst Screening For the Synthesis Of Cyclic Imides From Amentioning

confidence: 99%

See 2 more Smart Citations

Direct Synthesis of Cyclic Imides from Carboxylic Anhydrides and Amines by Nb₂O₅ as a Water‐Tolerant Lewis Acid Catalyst

et al. 2016

Self Cite

View full text Add to dashboard Cite

Abstract:In the 20 types of heterogeneous and homogenous catalysts screened, Nb2O5 shows the highest activity for synthesis of N-phenylsuccinimide by dehydrative condensation of succinic anhydride and aniline. Nb2O5 is applicable to the direct imidation a wide range of carboxylic anhydrides with NH3 or amines with various functional groups and is reusable. Kinetic studies show that Lewis acid catalysis of Nb2O5 is more water-tolerant than a Lewis acidic oxide (TiO2) and a homogeneous Lewis acid (ZrCl4), which results in higher yield of imides by Nb2O5.Cyclic imides and their derivatives are an important class of substrates for biological and chemical applications [1,2] and used as intermediates in the industrial production of drugs, dyes and polymers. [1a,1b,2] However, sustainable synthetic methods of cyclic imides from readily available starting materials are limited. General methods for synthesis of cyclic imides are the dehydrative condensation of a dicarboxylic acid [3] or its anhydride [3f,4,5] with an amine under harsh conditions (250-380 °C, ~330 bar) [3a,b] or under microwave heating, [5] and the cyclization of an amic acid with the help of acidic reagents or in the presence of excess amount of promoter (Lewis acid, base, dehydrating agent). These methods suffer from some of the drawbacks of low atom-efficiency, limited substrate scope, production of stoichiometric amount of byproducts, and need of special procedure (microwave heating). New synthetic routs from nitriles, [7] halides, [8] alkynes, [9] aryl boronic acids, [10] aromatic amides, [11] aliphatic amides, [12] cyclic amines [13] have been developed, but these homogeneous catalytic methods have drawbacks of low atom-efficiency, narrow substrate scope, needs of toxic reagents or additives, and difficulties in catalyst/products separation and catalyst reuse. For example, a reusable heterogeneous catalytic system by Pd/C[8d] suffers from needs of halides and CO as less environmentally benign reagents. One of the most effective synthesis of cyclic imides via dehydrogenative coupling of diols and amines (or nitriles) catalyzed by a Ru complex [1a,14] still suffers from limited substrate scope of diols and amines. Catalytic synthesis of cyclic imides by condensation of cyclic anhydrides with amines is one of the most deriable route. A few catalytic methods using TaCl5/SiO2 [15a,15b] or DABCO [15c] were reported to synthesize cyclic imides from cyclic anhydrides with amines. These methods [15] suffer from some of the drawbacks such as quite limited substrate scope, no results on the catalyst reuse, and needs of large catalyst loading and special method (microwave heating). [15a,15b] Potentially, the reaction is catalyzed by Lewis acid, but co-presence of water as byproduct can suppress Lewis acidity by hindering coordination. Inspired by recent reports that several metal oxides, such as Nb2O5, [16a] act as water-tolerant Lewis acid catalysts, [16] we have recently reported that Nb2O5 acts as water-tolerant Lewis acid catalyst for direct imida...

show abstract

Section: Catalyst Screening For the Synthesis Of Cyclic Imides From Amentioning

confidence: 99%

Section: Catalyst Screening For the Synthesis Of Cyclic Imides From Amentioning

confidence: 99%

Section: Catalyst Screening For the Synthesis Of Cyclic Imides From Amentioning

confidence: 99%

See 1 more Smart Citation

Direct Synthesis of Cyclic Imides from Carboxylic Anhydrides and Amines by Nb₂O₅ as a Water‐Tolerant Lewis Acid Catalyst

et al. 2016

Self Cite

View full text Add to dashboard Cite

show abstract

“…These imides were obtained by direct reaction of SAn with anilines in polyethylene glycol at 60 °C during 3–4 h. In 2014, Ali et al . synthesized cyclic amides from SA and n ‐octylamine using various metal oxides . Conventional solid Lewis acids showed moderate yields (61% for TiO 2 and 52% for γ‐Al 2 O 3 ).…”

Section: Materials Chemicals and Fuels From Succinic Acidmentioning

confidence: 99%

A review of progress in (bio)catalytic routes from/to renewable succinic acid

Mazière

Prinsen

García

et al. 2017

Biofuels Bioprod Bioref

View full text Add to dashboard Cite

In the last decade, succinic acid has become a key platform chemical in the bio‐based industry. It is one of the few renewable chemicals that have proven to be competitive with the fossil‐derived production. Still, improvements can be made in terms of sustainability, especially in the usage of alternative carbon sources for advanced life cycles. Numerous catalytic routes have been developed for the conversion of bio‐succinate to a wide range of chemical compounds and bio‐based polymers. However, most of them have been demonstrated from pure isolated succinic acid, but the isolation and purification of succinic acid from fermentation broths is no mean task and requires a considerable amount of energy. Therefore, catalytic routes in aqueous phase have also been studied intensively to by‐pass isolation and purification steps. This review describes the recent developments published in this research field. © 2017 Society of Chemical Industry and John Wiley & Sons, Ltd

show abstract

“…5–8), (3) dehydration reactions of alcohols and polyols (No. 9–16),, (4) nucleophilic substitution reactions of carboxylic acids (and their derivatives),, and (6) selective oxidation/dehydrogenation reactions …”

Section: Introductionmentioning

confidence: 99%

Lewis Acid Catalysis of Nb₂O₅ for Reactions of Carboxylic Acid Derivatives in the Presence of Basic Inhibitors

et al. 2018

Self Cite

View full text Add to dashboard Cite

This review focuses on catalytic applications of niobium pentoxide (Nb2O5) and niobic acid (Nb2O5 ⋅ nH2O). These materials serve as heterogeneous acid catalysts that show excellent activity and selectivity for various types of reactions including hydrations, dehydrations, and oxidations. Most recently, they have been used for dehydration reactions of polyols and nucleophilic substitution reactions of carboxylic acid derivatives. A special focus is placed on the latter reactions, where superficial Nb5+ cations act as Lewis‐acidic sites that activate oxygen‐containing functional groups of substrates even in the presence of basic inhibitors such as water or amines. This unique behavior of Nb‐oxide‐based catalysts is a consequence of their Lewis acidity, which is characterized by their ability to simultaneously activate C=O bonds but not to engage in strong competitive adsorption of base molecules. Both experimental and theoretical investigations are presented in order to assess the characteristic features of the Nb‐oxide‐based catalysts together with their structural features.

show abstract

Versatile and Sustainable Synthesis of Cyclic Imides from Dicarboxylic Acids and Amines by Nb₂O₅ as a Base‐Tolerant Heterogeneous Lewis Acid Catalyst

Cited by 35 publications

References 62 publications

Direct Synthesis of Cyclic Imides from Carboxylic Anhydrides and Amines by Nb₂O₅ as a Water‐Tolerant Lewis Acid Catalyst

Direct Synthesis of Cyclic Imides from Carboxylic Anhydrides and Amines by Nb₂O₅ as a Water‐Tolerant Lewis Acid Catalyst

A review of progress in (bio)catalytic routes from/to renewable succinic acid

Lewis Acid Catalysis of Nb₂O₅ for Reactions of Carboxylic Acid Derivatives in the Presence of Basic Inhibitors

Contact Info

Product

Resources

About

Versatile and Sustainable Synthesis of Cyclic Imides from Dicarboxylic Acids and Amines by Nb2O5 as a Base‐Tolerant Heterogeneous Lewis Acid Catalyst

Cited by 35 publications

References 62 publications

Direct Synthesis of Cyclic Imides from Carboxylic Anhydrides and Amines by Nb2O5 as a Water‐Tolerant Lewis Acid Catalyst

Direct Synthesis of Cyclic Imides from Carboxylic Anhydrides and Amines by Nb2O5 as a Water‐Tolerant Lewis Acid Catalyst

A review of progress in (bio)catalytic routes from/to renewable succinic acid

Lewis Acid Catalysis of Nb2O5 for Reactions of Carboxylic Acid Derivatives in the Presence of Basic Inhibitors

Contact Info

Product

Resources

About

Versatile and Sustainable Synthesis of Cyclic Imides from Dicarboxylic Acids and Amines by Nb₂O₅ as a Base‐Tolerant Heterogeneous Lewis Acid Catalyst

Direct Synthesis of Cyclic Imides from Carboxylic Anhydrides and Amines by Nb₂O₅ as a Water‐Tolerant Lewis Acid Catalyst

Direct Synthesis of Cyclic Imides from Carboxylic Anhydrides and Amines by Nb₂O₅ as a Water‐Tolerant Lewis Acid Catalyst

Lewis Acid Catalysis of Nb₂O₅ for Reactions of Carboxylic Acid Derivatives in the Presence of Basic Inhibitors