LASER FLASH-PHOTOLYSIS OF DITHIO-2,2'-DIPYRIDINE - STRUCTURE AND REACTIVITY OF PYRIDYL-2-THIO RADICAL

被引：51

作者：

ALAM, MM ^{[1
]}

WATANABE, A ^{[1
]}

ITO, O ^{[1
]}

机构：

[1] TOHOKU UNIV,INST CHEM REACT SCI,AOBA KU,SENDAI,MIYAGI 98077,JAPAN

来源：

JOURNAL OF ORGANIC CHEMISTRY | 1995年 / 60卷 / 11期

关键词：

D O I：

10.1021/jo00116a033

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

Photochemical reactions of dithio-2,2'-dipyridine were studied by the laser flash photolysis method to clarify the structure and reactivities of the intermediate radical. The transient absorption band appearing at 490 nm was attributed to a radical in which the unpaired electron was mainly localized at the sulfur atom, namely, pyridyl-2-thio radical (2-PyS(.)). The low reactivities of 2-PyS(.) to O-2 and hydrogen-atom donors were confirmed by the invariance of the decay rates of 2-PyS(.). The high reactivity of 2-PyS(.) in addition reactions to conjugated dienes was confirmed by the accelerated first-order decay rate of 2-PyS(.) upon addition of the diene. For example, the addition reaction rate constant for isoprene was 1.2 x 10(9) M(-1) s(-1) (in THF), which is higher than that of PhS(.). Such reactivities were interpreted by comparison with MO calculations.

引用

页码：3440 / 3444

页数：5

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