New Avenues of TMM Diradical Chemistry

在有机和大分子化学项目的支持下，加州大学圣巴巴拉分校化学和生物化学系的R. Daniel Little教授正在研究三甲基乙烷二自由基和1,3-二基自由基阳离子的反应化学。利用二氮烯作为双自由基前体，利特尔教授正在探索8元环碳环化合物或其6元环异构体以及含氧和含氮杂环类似物选择性形成的因素。对称和不对称的1,3-二基自由基阳离子是与7元和8元环化合物的组装有关的研究主题，以及阳离子自由基平衡的机制分析和伴随氮从二氮中损失的反冲。许多显示出有趣的化学或生物活性的有机化合物都含有7元或8元的原子环。特别是考虑到小环（5元和6元）化合物通常具有更大的稳定性，开发合成这种环状化合物的有效技术仍然是人们非常感兴趣的。加州大学圣巴巴拉分校化学与生物化学系的r·丹尼尔·利特尔（R. Daniel Little）教授正在开发新的反应，可以选择性地合成7元和8元环化合物，并研究导致这些反应选择性的因素。

With the support of the Organic and Macromolecular Chemistry Program, Professor R. Daniel Little, of the Department of Chemistry and Biochemistry at the University of California, Santa Barbara, is studying the reaction chemistry of trimethylenemethane diradicals and 1,3-diyl radical cations. Using diazenes as diradical precursors, Professor Little is exploring the factors responsible for selective formation of 8-membered ring carbocyclic compounds or their 6-membered ring isomers, as well as oxygen- and nitrogen-containing heterocyclic analogs. Symmetrical and unsymmetrical 1,3-diyl radical cations are the subjects of studies relating to the assembly of 7- and 8-membered ring compounds as well as mechanistic analyses of cation radical equilibration and recoil accompanying loss of nitrogen from diazenes.Many organic compounds which display interesting chemical or biological activity contain 7- or 8-membered rings of atoms. The development of efficient techniques for the synthesis of such cyclic compounds remains of great interest, particularly in light of the generally greater stability of smaller-ring (5- and 6-membered) compounds. Professor R. Daniel Little, of the Department of Chemistry and Biochemistry at the University of California, Santa Barbara, is developing new reactions allowing the selective synthesis of 7- and 8-membered ring compounds and studying the factors responsible for the selectivity of these reactions.