Temperature Dependent Photochemical Cleavage of 2,5-Dimethylphenacyl Esters

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F03%3A00008279" target="_blank" >RIV/00216224:14310/03:00008279 - isvavai.cz</a>

Výsledek na webu

—

DOI - Digital Object Identifier

—

Jazyk výsledku

angličtina

Název v původním jazyce

Temperature Dependent Photochemical Cleavage of 2,5-Dimethylphenacyl Esters

Popis výsledku v původním jazyce

The study of the temperature-sensitive photochemical release of a carboxylic acid from 2,5-dimethylphenacyl ester is reported. Quantum yields of the benzoate ester degradation in benzene increased from 0.22 at room temperature to 0.28 at 50 oC whereas amore significant increase (nearly by a factor of 3) was observed in methanol and ethanol, reaching a high reaction efficiency (0.25) typically found in non-polar solvents. The reaction proceeds predominantly via the triplet pathway and the E-photoenol inthe whole temperature range in methanol solution. A higher quantum efficiency in heated methanol is explained by enhancing the E-photoenol population. This picture was partially confirmed by the quantum chemical calculations. The 2,5-dimethylphenacyl chromophore is proposed as an efficient photoremovable protecting group for carboxylic acids in solutions under conventional or microwave-assisted heating for applications in organic synthesis, such as the solid-phase synthesis.

Název v anglickém jazyce

Temperature Dependent Photochemical Cleavage of 2,5-Dimethylphenacyl Esters

Popis výsledku anglicky

The study of the temperature-sensitive photochemical release of a carboxylic acid from 2,5-dimethylphenacyl ester is reported. Quantum yields of the benzoate ester degradation in benzene increased from 0.22 at room temperature to 0.28 at 50 oC whereas amore significant increase (nearly by a factor of 3) was observed in methanol and ethanol, reaching a high reaction efficiency (0.25) typically found in non-polar solvents. The reaction proceeds predominantly via the triplet pathway and the E-photoenol inthe whole temperature range in methanol solution. A higher quantum efficiency in heated methanol is explained by enhancing the E-photoenol population. This picture was partially confirmed by the quantum chemical calculations. The 2,5-dimethylphenacyl chromophore is proposed as an efficient photoremovable protecting group for carboxylic acids in solutions under conventional or microwave-assisted heating for applications in organic synthesis, such as the solid-phase synthesis.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

CC - Organická chemie

OECD FORD obor

—

Projekt

<a href="/cs/project/GA203%2F02%2F0879" target="_blank" >GA203/02/0879: Vliv mikrovlnného záření na fotochemické reakce</a><br>

Návaznosti

Z - Vyzkumny zamer (s odkazem do CEZ)

Rok uplatnění

2003

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Molecular Diversity

ISSN

1381-1991

e-ISSN

—

Svazek periodika

7

Číslo periodika v rámci svazku

2-4

Stát vydavatele periodika

CH - Švýcarská konfederace

Počet stran výsledku

7

Strana od-do

265

Kód UT WoS článku

—

EID výsledku v databázi Scopus

—