CO₂ utilization via carbonate-promoted C--H carboxylation and CO₂ hydrogenation
Abstract/Contents
- Abstract
- With the CO2 level in the atmosphere at 400 ppm and rising, finding new and efficient ways to recycle this greenhouse gas is of paramount importance. Most previous efforts have focused on converting CO2 to low-value C1 compounds such as CO, formic acid, methanol and methane. The use of CO2 as a feedstock for the synthesis of multi-carbon compounds is advantageous because these targets generally have higher value and greater energy density. The key chemical challenge is to form C--C bonds to CO2 without using energy-intensive reagents. Here we describe a novel carboxylation reaction in which a C--H bond and CO2 are transformed into a carboxylate (C--CO2--) using alkali carbonates as a promoter, in absence of any catalyst or solvent. Alkali carbonate salts are capable of deprotonating C--H bonds that are ordinarily weak acids (pKa> 40 in organic solvent) to generate carbanions (C--) at intermediate temperatures (200-360 °C). In the presence of CO2, the carbanions react rapidly to form carboxylates. The chemistry has been applied in the synthesis of 2,5-furandicarboxylic acid (FDCA) from 2-furoic acid, which can readily be made from lignocellulose. FDCA is an attractive green replacement for fossil fuel-derived terephthalic acid, used in polyethylene terephthalate (PET) polymer synthesis. Based on the above-described approach of C--C bond formation, we also demonstrate that a mixture of alkali carbonate, CO2 and H2 can be readily converted to formate, oxalate and other C2+ carboxylates like acetate, propionate and succinate. The reaction occurs at intermediate temperature and pressure and requires H2O vapor for hydrating the carbonate salt. Isotopic labelling studies are consistent with a mechanism that proceeds by a series of H2 and C--H deprotonations to form H-- and C-centred nucleophiles that undergo H--C and C--C bond formations.
Description
| Type of resource | text |
|---|---|
| Form | electronic resource; remote; computer; online resource |
| Extent | 1 online resource. |
| Place | California |
| Place | [Stanford, California] |
| Publisher | [Stanford University] |
| Copyright date | 2018; ©2018 |
| Publication date | 2018; 2018 |
| Issuance | monographic |
| Language | English |
Creators/Contributors
| Author | Banerjee, Aanindeeta |
|---|---|
| Degree supervisor | Kanan, Matthew William, 1978- |
| Thesis advisor | Kanan, Matthew William, 1978- |
| Thesis advisor | Stack, T. (T. Daniel P.), 1959- |
| Thesis advisor | Wandless, Thomas |
| Degree committee member | Stack, T. (T. Daniel P.), 1959- |
| Degree committee member | Wandless, Thomas |
| Associated with | Stanford University, Department of Chemistry. |
Subjects
| Genre | Theses |
|---|---|
| Genre | Text |
Bibliographic information
| Statement of responsibility | Aanindeeta Banerjee. |
|---|---|
| Note | Submitted to the Department of Chemistry. |
| Thesis | Thesis Ph.D. Stanford University 2018. |
| Location | electronic resource |
Access conditions
- Copyright
- © 2018 by Aanindeeta Banerjee
- License
- This work is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported license (CC BY-NC).
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