2007
2,5-Dimethylphenacyl carbamate: A photoremovable protecting group for amines and amino acids
KAMMARI, Laxminarayana, Lukáš PLÍŠTIL, Jakob WIRZ a Petr KLÁNZákladní údaje
Originální název
2,5-Dimethylphenacyl carbamate: A photoremovable protecting group for amines and amino acids
Název česky
2,5-Dimethylfenacylkarbamát jako fotoodštěpitelná chránicí skupina pro aminy a aminokyseliny
Autoři
KAMMARI, Laxminarayana (356 Indie), Lukáš PLÍŠTIL (203 Česká republika), Jakob WIRZ (756 Švýcarsko) a Petr KLÁN (203 Česká republika, garant)
Vydání
Photochemical and Photobiological Sciences, Cambridge, United Kingdom, Royal Society of Chemistry, 2007, 1474-905X
Další údaje
Jazyk
angličtina
Typ výsledku
Článek v odborném periodiku
Obor
10401 Organic chemistry
Stát vydavatele
Velká Británie a Severní Irsko
Utajení
není předmětem státního či obchodního tajemství
Impakt faktor
Impact factor: 2.208
Kód RIV
RIV/00216224:14310/07:00020037
Organizační jednotka
Přírodovědecká fakulta
UT WoS
000243204700005
Klíčová slova anglicky
Photochemistry; photoremovable protecting groups; amines; amino acids
Příznaky
Mezinárodní význam, Recenzováno
Změněno: 23. 6. 2009 15:13, prof. RNDr. Petr Klán, Ph.D.
V originále
2,5-Dimethylphenacyl (DMP) carbamates (1a-c) released the corresponding free amines or amino acid in high chemical yields, albeit with quantum yields of only 0.04-0.09, upon irradiation in either aprotic or protic solvents. The photoreaction proceeded principally from the triplet excited state via the E-photoenol. The lifetimes of the triplet enol and of the E- and Z-enols in the ground state were determined by laser flash photolysis. The primary photoinitiated transformation liberated a carbamic acid derivative, which subsequently decarboxylated to the amino group containing compound. Exhaustive irradiation of a DMP-protected aniline (1a) in acetonitrile did not provide aniline in quantitative chemical yields, because it was involved in reductive cleavage of the starting material as an electron donor, thereby decreasing the overall deprotection yield (86%). Phenylalanine methyl ester, liberated from 1c, was, however, obtained in excellent chemical yields (97%). It was also found that the carbamates, while thermally stable, released amines with higher quantum yields in acidic methanol solutions. The DMP chromophore is proposed as an excellent photoremovable protecting group for amino acids and, under specific conditions, also for amines in organic synthesis and biochemistry.
Česky
2,5-Dimethylphenacyl (DMP) carbamates (1a-c) released the corresponding free amines or amino acid in high chemical yields, albeit with quantum yields of only 0.04-0.09, upon irradiation in either aprotic or protic solvents. The photoreaction proceeded principally from the triplet excited state via the E-photoenol. The lifetimes of the triplet enol and of the E- and Z-enols in the ground state were determined by laser flash photolysis. The primary photoinitiated transformation liberated a carbamic acid derivative, which subsequently decarboxylated to the amino group containing compound. Exhaustive irradiation of a DMP-protected aniline (1a) in acetonitrile did not provide aniline in quantitative chemical yields, because it was involved in reductive cleavage of the starting material as an electron donor, thereby decreasing the overall deprotection yield (86%). Phenylalanine methyl ester, liberated from 1c, was, however, obtained in excellent chemical yields (97%). It was also found that the carbamates, while thermally stable, released amines with higher quantum yields in acidic methanol solutions. The DMP chromophore is proposed as an excellent photoremovable protecting group for amino acids and, under specific conditions, also for amines in organic synthesis and biochemistry.
Návaznosti
| GA203/05/0641, projekt VaV |
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| MSM0021622413, záměr |
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