| Project/Area Number |
11440213
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
物質変換
|
|---|
| Research Institution | Tokyo University of Agriculture and Technology |
|---|
Principal Investigator |
TAKEDA Takeshi Tokyo University of Agriculture and Technology, Department of Applied Chemistry, Professor, 工学部, 教授 (40111455)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
藤原 徹 東京農工大学, 工学部, 教務職員 (30211527)
アノグ・チャンドラ セーカー・レッディ 東京農工大学, 大学院・工学研究科, 助手 (70302916)
|
|---|
| Project Period (FY) |
1999 – 2001
|
| Project Status |
Completed (Fiscal Year 2001)
|
| Budget Amount *help |
¥13,800,000 (Direct Cost: ¥13,800,000)
Fiscal Year 2001: ¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 2000: ¥1,800,000 (Direct Cost: ¥1,800,000)
Fiscal Year 1999: ¥9,900,000 (Direct Cost: ¥9,900,000)
|
|---|
| Keywords | Thioacetal / Titanocene(II) / Carbene Complex / Cyclopropane / Allylsilane / Ring-closing Metathesis / Heterocycle / Intramolecular Carbonyl Olefination / gem-ジハロゲン化物 / 複素環化合物 / カルボニル・オレフィン化 / gem-ニハロゲン化物 / 共役ジエン / ケトン |
|---|
| Research Abstract |
In this study, new methods for the construction of fundamental carbon frameworks utilizing titanium-carbene complexes, prepared by the desulfurizarion of thioacetals with titanocene(II) species, were explored.
1. Intermolecular reactions of titanium-carbene complexes
The reaction of carbene complexes with nitriles proceeded via the formation of azatitariacyclobutene to produce acylation products in good yields. The treatmant of vinylcarbene complexes with tert-halides gave the vinyltitanium species, which reacted with terminal alkynes and aldehydes to produce the corresponding adducts. Various allylsilanes were prepared by the reaction of the carbene complexes generated from 1,3-bis(phenylthio)propenes possessing a trialkylsilylmethyl group.
2. Intramolecular reactions of titanium-carbene complexes
Thioacetals bearing a carbon-carbon double bond afforded the unsaturated cyclic compounds via the ring-closing metathesis process when being treated with titanocene(II) species. This reaction wa
… More
s successfully applied to the synthesis of various heterocycles such as cyclic amines, ethers, and sulfides. The ring-closing metathesis and subsequent oxidative cleavage of unsaturated thioacetals possessing a silyl ether moiety gave the Z-1 ,5-olefmic diols with high stereoselectivity. It was found that the esters and thiolesters bearing a thioacetal moiety were good substrates for the intramolecular carbonyl olefination giving a variety of unsaturated cyclic compounds. Using this method, regioselective preparation of enol ethers of cyclic ketones, synthesis of dihydrothiophenes, and transformation of carboxylic acids into o-hydroxy ketones have been achieved.
3. Reaction of organotitanium species generated from organic halides and titanocene(II)
The treatment of gem-dihalides having a terminal carbon-carbon double bond with the titanocene(II) species produced the bicyclic cyclopropanes. The 1,2-disubstituted cyclopropanes were also produced with high trans-selectivity by the reaction of 1,3-dihalides with the titanocene(II) reagent. Less
|
