HETEROCYCLE-METAL PI-COMPLEXES IN ORGANIC SYNTHESIS

区域和立体定向合成新方法的发展 高度取代的杂环（二氢-和四氢-吡喃， 呋喃、哌啶和吡咯）。 成功实现 所提出的化学方法应该为合成提供一种新的策略， 一般类别的有机分子， 活性（抗病毒、抗生素等）。 不饱和杂环（呋喃基、吡喃基、吡咯基、吡啶基）将是π- 与过渡金属部分络合以提供阳离子η 4-呋喃， η 5-吡喃基、η 4-吡咯和η 5-吡啶基物质， 依次与亲核试剂和亲电试剂反应， 制备高度衍生化的氧和氮杂环， 和刻板的方式。 π-络合物中的金属模板起作用， 一些有用的角色。 它将用于1）稳定，否则 2）活性不饱和杂环，用于与 亲核试剂，和3）控制的立体化学和区域化学的 将各种有机单元引入杂环核。

The development of new methods for the regio- and stereospecific synthesis of highly substituted heterocycles (dihydro- and tetrahydro- pyrans, furans, piperidines and pyrroles) is proposed. Successful achievement of the proposed chemistry should provide a novel strategy for the synthesis of general classes of organic molecules with demonstrated biologically activity (antiviral, antibiotics, etc.). Unsaturated heterocycles (furan, pyranyl, pyrrole, pyridinyl) will be pi- complexed to transition metal moieties to provide cationic eta4-furan, eta5-pyranyl, eta4-pyrrole, and eta5-pyridinyl species that will be reacted sequentially with nucleophiles and electrophiles in order to prepare highly derivatized oxygen and nitrogen heterocycles in a regio- and stereodefined manner. The metal template in the pi-complexes serves a number of useful roles. It will be used to 1) stabilize otherwise unstable species 2) active unsaturated heterocycles for reaction with nucleophiles, and 3) control the stereochemistry and regiochemistry of the introduction of various organic units to the heterocycle core.