New Syntheses of Highly Reactive and Functional Organometallic Compounds and its Application to Organic Syntheses

本研究取得了以下成果：含氨基的乙烯基硅烷的酸催化环化反应。吡咯烷的立体选择性合成在酸性催化剂存在下，含氨基的乙烯基硅烷通过吸电子基团保护，顺利地生成2-(硅甲基)吡咯烷。该环化反应用于2-二取代吡咯烷(n=3-5)的立体选择性合成。1-6-烯炔与烯丙基锡的径向环化反应和以锡烯醇酸盐为自由基转移剂的新自由基反应。在AEBN存在下，在β位带有稳定基团的烯丙基三丁基锡烷与1，6-烯炔顺利地反应生成含有锡基和烯丙基的环化产物。这种环化反应对于合成高官能化的5元碳环和杂环是有价值的。与β-氰基烯丙基锡的反应生成了一定量的双环[4.3]。…更多的非L烯和单环化产物。α-卤代酯、-腈、-酮与锡基烯醇酸盐的自由基引发反应，以中等至高产率得到相应的γ-酮类脱硫剂。这一均解过程被应用于锡烯醇酸盐、卤代烷和缺电子烯烃之间的三组分偶联反应。乙烯基硅烷的硅定向环化：四氢呋喃的立体选择性合成和四氢吡喃的硅定向立体选择性合成在含羟基的乙烯基硅烷的酸催化环化反应中发生在分子内。环化反应是通过立体选择性地将羟基乙烯基硅烷、(Z)-5-硅基-4-戊烯-L-醇与亚甲基链条上带有取代基的(Z)-5-硅基-4-戊烯-L-醇进行立体定向合成，顺利地经酸催化的环化反应，分别得到反-2，5-，顺-2，4-和反-2，3-二取代四氢呋喃，具有中等到高的立体选择性。锰酸盐种类：生成，并与亲电的三烷基锰(II)酸盐试剂反应生成硫甲基锰试剂，其中锰酸盐是还原剂而不是烷基化试剂。三烷基锰(II)酸盐试剂的还原行为为直接生成一类新的具有结构变化的试剂提供了一种方法，生成的硫甲基锰试剂与烯丙基溴化物、烯酮和醛反应。找到了在铜(I)盐催化下用二硅烷将硅基引入α，β-酮的新方法。二硅烷与铜(I)盐的反应有效地诱导了硅-硅键的裂解生成硅基亲核试剂，其与α，β-不饱和烯酮的1，4-加成反应顺利进行。该反应被成功地应用于六甲基二硅烷，生成了迄今不易获得的三甲基硅基亲核试剂。前所未有的锰介导反应：生成非稳定的羰基叶立德。活化的锰以双(氯甲基)醚为前驱体生成非稳定的羰基叶立德，使用该体系以锰为还原剂，叶立德与缺电子的偶极化合物无需被还原剂直接还原。较少

The following results are obtained in this research project.Acid-Catalyzed Cyclization ofVinylsilanes Bearing an Amino Group. Stereoselective Synthesis ofPyrrolidinesIn the presence of an acid catalyst, vinylsilanes bearing an amino group protected by an electron-withdrawing group were smoothly bychzed to 2-(silylmethyl) pyrrolidines. This cyclization was utilized for the Stereoselective synthesis of 2 ndisubstituted pyrrqlidines (n = 3-5).Radical Cyclization of 1-6-Enynes Using Allylstannanes and New Radical Reactions Using Stannyl Enolates as Radical Transfer AgentsIn the presence of AEBN, allyltributylstannanes bearing a radical-stabilizing group at the β-position smoothly reacted with 1,6-enynes to give cyclized products incorporated with the stannyl and allyl groups in moderate to good yields This cyclization is valuable for the synthesis of highly functionalized 5-membered carbocycles and heterocycles The reactions with β-cyanoallylstannane formed a certain amount of bicyclo[4.3. … More 0]non-l-enes along with monocyclized products. The radicaHmtiated reactions of α-halo-esters, -nitriles, and -ketones with stannyl enolates gave the corresponding γ-keto denvatives in moderate to high yields. This homolytic process was applied to the three-component coupling reaction among stannyl enolates, haloalkanes, and electron-deficient alkenes.Silicon-directed Cyclization of Vinylysilanes : Stereoselective Synthesis of Tetrahydrofurans and TetrahydropyransSilicon-directed Stereoselective syn addition of hydroxy group to olefmic double bond occurs intramolecularly in an acid-catalyzed cyclization of vinylsilanes bearing hydroxy group. The cyclization proceeds by stereospecific syn addition of the hydroxy group Vinylsilanes, (Z)-5-silyl-4-penten-l-ols bearing a substituent on the methylene tether, smoothly undergo the acid-catalyzed cyclization to give trans-2,5-, cis-2,4-, and trans-2,3-disubstituted tetrahydrofurans respectively, with moderate to high stereoselectivitv.Manganese Ate Species: Generation,and Reactions with ElectrophilesTrialkylmanganese (II) ate reagents, "RMnLi" reacted with iodomethylsulfides to produce thiomethylmanganese reagents, where the manganate serves as a reductant not an alkylation agent. The reductive behavior of trialkylmanganese (II) ate reagents provides a protocol for the direct generation of a new class of reagents thiomethylmanganese reagents with structural variety, and the generated thiomethylmanganese reagents reacted with allyl bromides, enones and aldehydes.New Method for Introduction of a Silyl Group into α,β-Enones Using a Disilane Catalyzed by a Copper(I) salt.The reaction of a disilane with a Cu(I) salt efficiently induces cleavage of the Si-Si bond to generate a silyl nucleophile in aprotic polar solvent and its 1,4-addition to α,β-unsaturated enones smoothly proceeds with a catalytic amount of a Cu(I) salt were found. This reaction is successfully applied to hexamethyldisilane to generate a trimethylsilyl nucleophile hitherto not easily accessible.Unprecedented Manganese-Mediated Reactions : Generation of Non-Stabilized Carbonyl Ylids.Activated manganese generates nonstabilized carbonyl ylides from bis (chloromethyl) ethers as a precursor, and using this system with manganese as a reductant, the reactions of the ylides with electron-deficient dipolarophiles can be attained without the direct reduction of dipolarophiles by the reductant. Less