New Reactions Using Highly Functional Organometallic Compounds and its Application to Synthetic Chemistry

高功能有机金属化合物的新反应及其在合成化学中的应用

基本信息

批准号：
08454228
负责人：
HOSOMI Akira
金额：
$ 5.06万
依托单位：
University of Tsukuba
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1997
项目状态：
已结题

项目摘要

The following results are obtained in this research project.1.Silicon-directed Cyclization of Vinylysilanes : Stereoselective Synthesis of Tetrahydrofuranes and TetrahydropyranesSilicon-directed stereoselective syn addition of hydroxy group to olefinic double bond occurs intramolecularly in an acid-catalyzed cyclization of vinylsilanes bearing hydroxy group. Thus 5-dimethylphenylsilyl-4-penten-1-ol is smoothly cyclized to 2- (dimethylphenylsilyl) methyltetrahydrofuran upon the treatment of a catalytic amount of p-toluenesulfonic acid (TsOH) or TiCl_4.2.Unprecedented Samarium-Mediated Reactions : Generation of Non-Stabilized Carbonyl YlidsSamarium reveals a strong reducing ability and by virtue of this character together with its oxophilicity, is widely applied to organic synthesis in the formation of carbon-carbon bonds and transformation of a variety of functionalities with high selectivities. In the course of our study on the generation and reactions of reactive species, we report he … More rein the generation of novel active species, non-stabilized carbonyl ylids from iodomethyl silyl ethers mediated by samarium, otherwise inaccessible, and their [3+2] cycloadditions to a variety of unsaturated compounds such as aldehydes, alkenes, allenes, and alkynes.3.Manganese AteSpecies : Generation and Reactions with ElectrophilesTetrabutylmanganese ate complex 'Bu_4MnLi_2' reacts with allylic and prop-2-ynylic bromides to generate the corresponding allyl-and prop-2-ynyl-manganese species which further react with electrophiles such as aldehydes, ketones, epoxide, and chlorosilanes to afford the corresponding allylated and prop-2-ynylated and/or allenylated products in high yields.4.Allylstannylation of Alkynes and Alkenes via a Radical Process : Stereoselective Synthesis of Di-and Tri-Substituted VinylstannanesIn the presence of AIBN,allylstannanes bearing an electron-withdrawing group at the beta-position easily reacted with terminal and electron-deficient internal alkynes to give beta-allyl-substituted vinylstannanes in moderate to good yields. The allylstannylation proceeds with anti addition exclusively. Allylstannanes bearing an electron-withdrawing group at the beta-position easily reacted with various electron-deficient alkenes to introduce both the allyl and stannyl groups. Less

本研究项目取得了以下成果：1.乙烯基硅烷的硅定向环化：四氢呋喃和四氢吡喃的立体选择性合成在酸催化含羟基乙烯基硅烷的环化过程中，羟基与烯属双键的硅定向立体选择性顺加成发生在分子内。。因此在催化量的对甲苯磺酸 (TsOH) 或 TiCl_4.2 处理后，5-二甲基苯基甲硅烷基-4-戊烯-1-醇顺利环化为 2-(二甲基苯基甲硅烷基)甲基四氢呋喃。前所未有的钐介导反应：生成非-稳定的羰基钐具有很强的还原能力，并且凭借这种特性及其亲氧性，被广泛应用于有机合成中碳-碳键的形成和各种高选择性官能团的转化。他控制了新型活性物质的生成，由钐介导的碘甲基甲硅烷基醚产生非稳定的羰基叶立德，否则无法获得，以及它们与各种不饱和化合物的[3+2]环加成3. 锰酸类化合物：生成及其与亲电试剂的反应四丁基锰酸络合物“Bu_4MnLi_2”与烯丙基和丙-2-炔基溴化物反应生成相应的烯丙基-和丙-2-炔基-锰物质进一步与醛、酮、环氧化物等亲电子试剂发生反应氯硅烷以高产率提供相应的烯丙基化和丙-2-炔基化和/或丙烯基化产物。4.通过自由基过程对炔烃和烯烃进行烯丙基甲锡烷基化：二取代和三取代乙烯基锡烷的立体选择性合成在AIBN存在下，带有烯丙基锡烷β位的吸电子基团很容易与末端和缺电子的内部炔烃反应，得到β-烯丙基取代的乙烯基锡烷的产率中等至良好。在β位带有吸电子基团的烯丙基锡烷很容易与各种缺电子烯烃反应，引入烯丙基和甲锡烷基。