Mechanistic Studies on Garratt–Braverman Cyclization: The Diradical–Cycloaddition Puzzle
作者:Joyee Das、Subhendu Sekhar Bag、Amit Basak
DOI:10.1021/acs.joc.6b00490
日期:2016.6.3
In this work, we present the results of extensive multiprong studies involving the fate of deuterium-labeled substrates, EPR, trapping experiments, and LA-LDI mass spectrometry to sort out the controversies relating to the mechanism of Garratt–Braverman cyclization in two systems, namely bis-propargyl sulfones and ethers. The results are in conformity with a diradical mechamism for the sulfone, while
在这项工作中,我们介绍了涉及氘标记底物命运,EPR,捕获实验和LA-LDI质谱的广泛多方研究的结果,以理清与Garratt-Braverman环化机理在两个系统中有关的争议,即双炔丙基砜和醚。结果与砜的双自由基机理相符,而对于醚,阴离子[4 + 2]似乎是优选的途径。这表明向GB环化的机理途径取决于桥接炔丙基臂的杂原子(砜中的O或S)的性质。