TY - JOUR
T1 - In vitro condensation of amino acids in aqueous media
T2 - A synthesis driven by catalytic carbon monoxide oxidation
AU - Remias, Joseph E.
AU - Elia, Christine
AU - Grove, Laurie E.
AU - Sen, Ayusman
N1 - Funding Information:
The authors thank Dr. A. Daniel Jones for assistance in HPLC/MS method development and Prof. Timothy Glass for insightful comments. The authors thank the NSF for financial support. J.E.R. thanks the NCER/EPA STAR Fellowship for funding.
PY - 2006/6/1
Y1 - 2006/6/1
N2 - A novel mechanism is proposed for amino acid condensations to oligopeptides in aqueous media. The palladium-catalyzed condensation appears to proceed through a mechanism involving the Pd(0)/Pd(II) redox cycle. The reaction requires the use of carbon monoxide and an oxidant, and it is proposed that the oxidation of carbon monoxide to carbon dioxide drives the otherwise thermodynamically uphill condensation. The reaction occurs for several amino acids including glycine, alanine, β-alanine, and 5-aminopentanoic acid. Competition studies between glycine and alanine reveal steric effects on product formation. Dipeptides are the predominant condensation products, though some longer chains, containing up to 4 amino acids, can be observed. First-order plots for dipeptide appearance show an inverse, secondary, isotope effect consistent with the rate determining carboxylic-carbamic anhydride formation.
AB - A novel mechanism is proposed for amino acid condensations to oligopeptides in aqueous media. The palladium-catalyzed condensation appears to proceed through a mechanism involving the Pd(0)/Pd(II) redox cycle. The reaction requires the use of carbon monoxide and an oxidant, and it is proposed that the oxidation of carbon monoxide to carbon dioxide drives the otherwise thermodynamically uphill condensation. The reaction occurs for several amino acids including glycine, alanine, β-alanine, and 5-aminopentanoic acid. Competition studies between glycine and alanine reveal steric effects on product formation. Dipeptides are the predominant condensation products, though some longer chains, containing up to 4 amino acids, can be observed. First-order plots for dipeptide appearance show an inverse, secondary, isotope effect consistent with the rate determining carboxylic-carbamic anhydride formation.
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U2 - 10.1016/j.ica.2005.12.043
DO - 10.1016/j.ica.2005.12.043
M3 - Article
AN - SCOPUS:33646531601
SN - 0020-1693
VL - 359
SP - 2956
EP - 2965
JO - Inorganica Chimica Acta
JF - Inorganica Chimica Acta
IS - 9
ER -