Polymer Supported Triphenylphosphine-Palladium Acetate Complex PS-TPP-Pd(OAc)2 as a Heterogeneous and Reusable Catalyst for Indirect Reductive Amination of Aldehydes
Abstract
:1. Introduction
2. Results and Discussion
2.1. Effect of Catalyst Loading
Entry | Catalyst conc. mol-% | (%) Yield by G.C. |
---|---|---|
1 | 2.5 | 19 |
2 | 5 | 65 |
3 | 10 | 74 |
4 | 15 | 74 |
2.2. Effect of Various Solvents on the Reaction
Entry | Solvent | (%) Yield by G.C. |
---|---|---|
1 | Toluene | Traces |
2 | Ethanol | 47 |
3 | Dioxane | 18 |
4 | DMF | 74 |
5 | Acetontrile | 12 |
2.3. Effect of Temperature on the Reaction
Entry | Temp °C | (%) Yield by G.C. |
---|---|---|
1 | 40 | 58 |
2 | 50 | 64 |
3 | 60 | 71 |
4 | 70 | 72 |
5 | 85 | 74 |
6 | 95 | 69 |
2.4. Effect of Time on Reaction Yields
Entry | Time (h) | (%) Yield by G.C. |
---|---|---|
1 | 2 | 56 |
2 | 3 | 64 |
3 | 4 | 70 |
4 | 5 | 73 |
5 | 6 | 74 |
6 | 7 | 72 |
2.5. Preparation and Evaluation of PS-TPP-Pd(OAc)2 Complex Catalyst Varying Ratio of Pd(OAc)2 to PS-TPP
Entry | Pd/P Ratio | Pd(OAc)2 (mol-%) | PS-TPP (mol-%) | Color changes | (%) Yield by G.C. |
---|---|---|---|---|---|
1 | 1:1 | 10 | 10 | Black | 23 |
2 | 1:2 | 10 | 20 | Black | 45 |
3 | 1:3 | 10 | 30 | Brown-black | 65 |
4 | 1:4 | 10 | 40 | Yellow | 74 |
5 | 1: 5 | 10 | 50 | Yellow | 74 |
6 b | 1:4 | 10 | --- | Yellow | 75 |
2.6. Effect of Formic Acid Salts in Reduction of Amine
Entry | Hydrogen donor | Hydrogen donor (mmol) | (%) Yield by G.C. |
---|---|---|---|
1 | HCOONa | 1.5 | 67 |
2 | HCOONa | 2 | 71 |
3 | HCOONa | 2.5 | 73 |
4 | HCOONa | 3 | 74 |
5 | HCOOK | 3 | 59 |
6 | HCOONH4 | 3 | 21 |
2.7. Reductive Amination of Aldehydes Using Sodium Formate
Entry | Aldehyde | Amine | Product | %Yield b |
---|---|---|---|---|
1 | | | | 74 |
2 | | | | 84 |
3 | | | | 56 |
4 | | | | 85 |
5 | | | | 76 |
6 | | | | 82 |
7 | | | | 84 |
8 | | | | 77 |
9 | | | | 68 |
10 | | | | 65 |
11 | | | | 70 |
12 | | | | 58 |
13 | | | | 61 |
2.8. Recycle Study of Catalyst
Entry | Catalyst recycle number | Yield (%) b |
---|---|---|
1 | 0 | 74 |
2 | 1 | 71 |
3 | 2 | 68 |
4 | 3 | 66 |
5 | 4 | 65 |
3. Experimental Section
3.1. General
3.1.1. Preparation of Polymer Supported Triphenyphosphane Palldium Acetate PS-TPP-Pd(OAc)2 Complex [15,16,17,18,19]
3.1.2. Stage No. 1, Preparation of Imine
3.1.3. Stage No. 2, Reduction of Imine
3.1.4. Recovery and Recycle of PS-TPP-Pd(OAc)2 Catalyst
3.1.5. Characterization Data of Products
4. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Ekbote, S.S.; Gadge, S.T.; Bhanage, B.M. Polymer Supported Triphenylphosphine-Palladium Acetate Complex PS-TPP-Pd(OAc)2 as a Heterogeneous and Reusable Catalyst for Indirect Reductive Amination of Aldehydes. Catalysts 2014, 4, 289-298. https://doi.org/10.3390/catal4030289
Ekbote SS, Gadge ST, Bhanage BM. Polymer Supported Triphenylphosphine-Palladium Acetate Complex PS-TPP-Pd(OAc)2 as a Heterogeneous and Reusable Catalyst for Indirect Reductive Amination of Aldehydes. Catalysts. 2014; 4(3):289-298. https://doi.org/10.3390/catal4030289
Chicago/Turabian StyleEkbote, Sunil S., Sandip T. Gadge, and Bhalchandra M. Bhanage. 2014. "Polymer Supported Triphenylphosphine-Palladium Acetate Complex PS-TPP-Pd(OAc)2 as a Heterogeneous and Reusable Catalyst for Indirect Reductive Amination of Aldehydes" Catalysts 4, no. 3: 289-298. https://doi.org/10.3390/catal4030289