Department of Chemistry, University of Rochester, Rochester, New York 14627, United States.
J Org Chem. 2021 Jun 4;86(11):7508-7514. doi: 10.1021/acs.joc.1c00504. Epub 2021 May 25.
Nanosecond transient absorption spectroscopy was used to generate ethoxyl radicals and demonstrate that they react with 2,6-lutidine and 4-phenylpyridine to give the corresponding -hydropyridinyl radicals-products of a novel hydrogen atom transfer from the alkoxyl radical to the nitrogen atom of the substituted pyridines. Nanosecond kinetics show that both reactions are rapid ( ∼ 10 M s) in acetonitrile at room temperature. Rate constants measured for reaction of the ethoxyl vs. -ethoxyl radical with 2,6-lutidine and 4-phenylpyridine show that both reactions exhibit primary H/D kinetic isotope effects for the hydrogen (deuterium) atom transfer reactions.
纳秒瞬态吸收光谱被用来产生乙氧基自由基，并证明它们与 2,6- 二甲基吡啶和 4- 苯基吡啶反应，生成相应的 - 氢吡啶基自由基 - 这是一种从烷氧基自由基到取代吡啶氮原子的新型氢原子转移产物。纳秒动力学表明，这两个反应在室温下的乙腈中都很快（∼10M s）。测量乙氧基自由基与 2,6- 二甲基吡啶和 4- 苯基吡啶反应的速率常数表明，两个反应都表现出氢（氘）原子转移反应的一级 H/D 动力学同位素效应。
