Reaction of {LiC6H2−2,4,6‐Cyp3⋅Et2O}2(Cyp=cyclopentyl) (
We have been interested in the development of rubisco‐based biomimetic systems for reversible CO2capture from air. Our design of the chemical CO2capture and release (CCR) system is informed by the understanding of the binding of the activator CO2(ACO2) in rubisco (ribulose‐1,5‐bisphosphate carboxylase/oxygenase). The active site consists of the tetrapeptide sequence Lys‐Asp‐Asp‐Glu (or KDDE) and the Lys sidechain amine is responsible for the CO2capture reaction. We are studying the structural chemistry and the thermodynamics of CO2capture based on the tetrapeptide CH3CO−KDDE−NH2(“KDDE”) in aqueous solution to develop rubisco mimetic CCR systems. Here, we report the results of1H NMR and13C NMR analyses of CO2capture by butylamine and by KDDE. The carbamylation of butylamine was studied to develop the NMR method and with the protocol established, we were able to quantify the oligopeptide carbamylation at much lower concentration. We performed a pH profile in the multi equilibrium system and measured amine species and carbamic acid/carbamate species by the integration of1H NMR signals as a function of pH in the range 8≤pH≤11. The determination of Δ
- NSF-PAR ID:
- 10418420
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemPhysChem
- Volume:
- 24
- Issue:
- 11
- ISSN:
- 1439-4235
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Reaction of {LiC6H2−2,4,6‐Cyp3⋅Et2O}2(Cyp=cyclopentyl) (
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