New phototriggers:: Extending the p-hydroxyphenacyl π-π* absorption range

被引：55

作者：

Conrad, PG ^{[1
]}

Givens, RS ^{[1
]}

Weber, JFW ^{[1
]}

Kandler, K ^{[1
]}

机构：

[1] Univ Kansas, Dept Chem, Lawrence, KS 66045 USA

来源：

ORGANIC LETTERS | 2000年 / 2卷 / 11期

关键词：

D O I：

10.1021/ol005856n

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

[GRAPHICS] Introducing 3-methoxy or 3,5-dimethoxy substituents on the 4-hydroxyphenacyl (pHP) photoremovable protecting group has been explored with two excitatory gamma-amino acids, L-glutamic acid and gamma-amino butyric acid (GABA)., These substituents significantly extend the absorption range of the pHP chromophore, e.g., the tail of absorption bands of 2a,b extend above 400 nm, well beyond the absorptions of aromatic amino acids and nucleotides. Irradiation releases the amino acids with rate constants of similar to 10(7) s(-1) and appearance efficiencies (Phi(app)) of 0.03-0.04. The photoproducts are formed through the pHP excited triplet and are primarily products of photoreduction and photohydrolysis, 1a,b also rearranged to the phenylacetic acid 3.

引用

页码：1545 / 1547

页数：3

共 16 条

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[2] Direct photolysis of phenacyl protecting groups studied by laser flash photolysis: An excited state hydrogen atom abstraction pathway leads to formation of carboxylic acids and acetophenone [J].