Synthesis of Polyfunctionalyzed Molecules Using Cooperative Interactions between Multiple Elements

利用多种元素之间的协同相互作用合成多官能化分子

• 批准号: 11650888
• 负责人: SEGI Masahito
• 金额: $ 2.3万
• 依托单位: Kanazawa University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11650888/
• 关键词: Hydrozirconation; Phenylseleno Group; Vinylzirconocene; Dimethyltitanocene; Selenolester; Allylic Selenide; Selenoxide Elimination; [2,3]Sigmatropic Rearrangement; オレフィン化; アルケニルセレニド; トランスメタル化; 高次有機銅試薬; ジルコナシクロペンテン

Terminal alkynes (1) having a PhSe group on α or β carbonn atom contain three reactive sites (C-C triple bond, terminal alkynic hydrogen atom, PhSe group). Generally, hydrometalation of terminal alkynes takes place stereospecifically to give the E-alkenic metal species which are replaced by some electrophiles such as aldehydes, epoxides, and acyl halides to construct a new carbon-carbon bond. On the other hand, organoselenium chemistry became a very powerful tool in organic synthesis in recent times. Of particular importance is the owing to its easily handled nature.1 reacted with zirconocene-ethylene complex to give regioselectively zirconacyclopentene derivatives. Hydrozirconation of 1 with Cp_2ZrHCl followed by transmetalation with Me_2Zn gave the corresponding terminal vinylzinc intermediates regio-and stereoselectively, which underwent the coupling reaction with aldehydes to afford the allylic alcohol derivatives having a phenylseleno group. Terminal hydrogen atom of 1 was easily abstracted by n-BuLi at-78℃ to generate sp carbanion species which were effectively trapped by aldehydes on epoxides. The compounds with a phenylseleno group were oxidized with excess amounts of H_2O_2 to yield the desired products having A-shaped olefinic alcohol moiety in good yields via selenoxide syn elimination.Methylenation of phenylselenolesters with dimethyl titanocene (Cp_2TiMe_2) gave alkenyl selenides, which were subjected to oxidation with m-CPBA to afford terminal alkynes, not to allene, via selenoxide syn elimination. On the other hand, reaction of α-phenylseleno ketones with Cp_2TiMe_2 gave a mixture of isomeric allylic selenides and the subsequent oxidation by H_2O_2 led to the formation of allylic alcohols via [2,3] sigmatropic rearrangement.

在α或β碳原子上带有PhSe基团的端炔（1）含有三个反应活性中心（C-C三键、端炔氢原子、PhSe基团）。通常，末端炔的加氢金属化立体特异性地发生以得到E-烯属金属物质，其被一些亲电试剂如醛、环氧化物和酰卤取代以构建新的碳-碳键。另一方面，有机硒化学近年来成为有机合成中非常有力的工具。特别重要的是，由于其易于处理的性质。1与锆茂-乙烯络合物反应，区域选择性地得到锆环戊烯衍生物。1与Cp_2ZrHCl的锆氢化反应和与Me_2Zn的金属转移反应，区域和立体选择性地得到相应的末端乙烯基锌中间体，再与醛发生偶联反应，得到含苯硒基的烯丙醇衍生物。在-78 ℃下，1的末端氢原子容易被n-BuLi夺取，生成sp碳负离子物种，这些物种被醛有效地捕获在环氧化物上。用过量的H_2O_2氧化含苯硒基的化合物，通过硒醚顺式消除反应，以较好的产率得到含A型烯醇结构的产物，苯硒醇酯与二茂钛（Cp_2TiMe_2）发生亚甲基化反应，得到烯基硒醚，再用m-CPBA氧化，通过硒醚顺式消除反应，得到端炔而不是丙二烯。另一方面，α-苯硒酮与Cp_2TiMe_2反应生成烯丙基硒醚的混合物，随后被H_2O_2氧化，通过[2，3] σ转移重排生成烯丙基醇。

项目成果

Masahito Segi: "Conjugate Addition of Vinylic Organocuprates Generated via Transmetalation of PhSe-Substituted Vinylzirconates."Tetrahedron Letters. (in press).

Masahito Segi：“通过 PhSe 取代的乙烯基锆酸盐的金属转移生成乙烯基有机铜酸盐的共轭加成。”四面体字母。

Guang Ming Li: "On the Behavior of α, β-Unsaturated Thioaldehydes and Thioketones in the Diels-Alder Reaction."The Journal of Organic Chemistry. 65. 6601-6612 (2000)

李光明：“关于 α, β-不饱和硫醛和硫酮在 Diels-Alder 反应中的行为。”有机化学杂志 65. 6601-6612 (2000)

Masahito Segi: "Conjugate Addition of Vinylic Organocuprates Generated via Transmetalation of PhSe-Substituted Vinylzirconates"Tetrahedron Letters. (発表予定).

Masahito Segi：“通过 PhSe 取代的乙烯基锆酸盐的金属转移生成乙烯基有机铜酸盐的共轭加成”四面体快报（待出版）。

Shuji Tomoda: "Reversal of π-Facial Diastereoselection in the Hydride Reduction of Selenanones Further Application of the Exterior Frontier Orbital Extension Model"Tetrahedron Letters. 41. 4597-4601 (2000)

Shuji Tomoda：“硒酮氢化物还原中 π 面非对映选择的逆转，外边界轨道扩展模型的进一步应用”四面体快报 41。 4597-4601 (2000)

Masahito Segi: "Regioselective Carbon-Selenium Bond Forming Reaction of Zirconacycles with Phenylselenenyl Halides."Tetrahedron Letters. (発表予定).

Masahito Segi：“锆环与苯基硒基卤化物的区域选择性碳-硒键形成反应”（即将出版）。