32570-25-5Relevant academic research and scientific papers
An expeditious and highly efficient synthesis of substituted pyrroles using a low melting deep eutectic mixture
Alvi, Shakeel,Ali, Rashid
, p. 9732 - 9745 (2021/12/01)
An expeditious green method for the synthesis of diverse valued substituted pyrroles through a Paal-Knorr condensation reaction, using a variety of amines and 2,5-hexanedione/2,5-dimethoxytetrahydrofuran in the presence of a low melting mixture ofN,N’-dimethylurea andL-(+)-tartaric acid (which acts as a dual catalyst/solvent system), has fruitfully been revealed. Herein, we have disclosed the applicability of this simple yet effective strategy for the generation of mono- and dipyrroles in good to excellent yields. Moreover,C3-symmetric tripyrrolo-truxene derivatives have also been assembled by means of cyclotrimerization, Paal-Knorr and Clauson-Kaas reactions as crucial steps. Interestingly, the melting mixture was recovered and reused with only a gradual decrease in the catalytic activity (over four cycles) without any significant drop in the yield of the product. This particular methodology is simple, rapid, environmental friendly, and high yielding for the generation of a variety of pyrroles. To the best of our knowledge, the present work reveals the fastest greener method reported up to this date for the construction of substituted pyrroles by utilizing the Paal-Knorr synthetic protocol, achieving impressive yields under operationally simple reaction conditions without involving any precarious/dangerous catalysts or unsafe volatile organic solvents.
A mild and efficient method for the synthesis of pyrroles using MIL-53(Al) as a catalyst under solvent-free sonication
Nguyen, Hai Truong,Thuy Nguyen, Linh Ho,Le Hoang Doan, Tan,Tran, Phuong Hoang
, p. 9093 - 9098 (2019/03/28)
A highly efficient method for the synthesis of pyrroles using MIL-53(Al) as a catalyst has been developed under solvent-free sonication. This reaction has a broad substrate scope and high yields were obtained within a short reaction time. Remarkably, no additional additives and volatile organic solvent are required for this method and the MIL-53(Al) could be recovered and reused several times without significant drop-off in catalytic activity.
New nano-Fe3O4-supported Lewis acidic ionic liquid as a highly effective and recyclable catalyst for the preparation of benzoxanthenes and pyrroles under solvent-free sonication
Nguyen, Hai Truong,Thi Le, Ngoc-Phuong,Nguyen Chau, Duy-Khiem,Tran, Phuong Hoang
, p. 35681 - 35688 (2018/10/31)
A novel magnetic nanomaterial-immobilized Lewis acidic ionic liquid was successfully synthesized by the covalent embedding of 3-(3-(trimethoxysilyl)propyl)-1H-imidazol-3-ium chlorozincate (ii) ionic liquid to the surface of Fe3O4 nanoparticles. The material was then characterized by FT-IR, SEM, TEM, TGA, ICP-OES, Raman, and EDS. Its performance as a new-generation Lewis acidic catalyst was also examined on the ultrasound-mediated synthesis of benzoxanthenes and pyrroles. Upon completion, the catalyst was simply recovered by an external magnet for multiple reuses without significant lessening of catalytic performance.
A green and efficient method for the synthesis of pyrroles using a deep eutectic solvent ([CholineCl][ZnCl2]3) under solvent-free sonication
Truong Nguyen, Hai,Nguyen Chau, Duy-Khiem,Tran, Phuong Hoang
, p. 12481 - 12489 (2017/11/06)
An efficient deep eutectic solvent-based synthesis of pyrroles under ultrasound irradiation has been developed to provide a significant improvement of the yield up to 99% in a short reaction time. The synthesis of pyrroles is highly atom-economical, producing water as the sole byproduct. In addition, [CholineCl][ZnCl2]3 is easily synthesized from commercially available choline chloride and zinc chloride via a cost-effective and environmentally benign pathway. The obtained [CholineCl][ZnCl2]3 has been characterized by FT-IR, 1H-NMR, 13C-NMR, HRMS (ESI), Raman, and TGA. Five new pyrroles are synthesized by the current method. Moreover, [CholineCl][ZnCl2]3 could be reused up to four times without significant loss of catalytic activity.
Triazole-Au(I) complexes: A new class of catalysts with improved thermal stability and reactivity for intermolecular alkyne hydroamination
Duan, Haifeng,Sengupta, Sujata,Petersen, Jeffrey L.,Akhmedov, Novruz G.,Shi, Xiaodong
supporting information; experimental part, p. 12100 - 12102 (2009/12/30)
(Chemical Equation Presented) A series of 1,2,3-triazole-bound cationic Au(I) catalysts have been synthesized, and their structures have been characterized by X-ray crystallography. Variable-temperature NMR studies revealed dynamic triazole-Au cation coor
