テトラ置換および機能化されたエノールエーテルを,イノラートによるエステルのE選択的オレフィネーションによって合成する
Mitsuru Shindo1, Taisuke Kita, Toshihiro Kumagai
1Institute of Health Biosciences, The University of Tokushima Graduate School, Japan. shindo@cm.kyushu-u.ac.jp
Journal of the American Chemical Society
|January 26, 2006
まとめ
研究者は,エステルカルボニルのE選択的オレフィネーションのための新しい方法を開発し,機能化されたオレフィンを生成しました. 彼らはまた,チオールエステルにC-S挿入を達成し,イノラートを使用してβ-ケトチオールエステルを生成しました.
科学分野:
- 有機化学 オーガニック・ケミストリー
- 合成化学 合成化学について
背景:
- オレフィネーション反応は,複雑な有機分子を合成するために極めて重要です.
- 高度に置換されたオレフィンを生成するための選択的方法の開発は,依然として課題です.
研究 の 目的:
- カーボニルエステルの新しいE選択的オレフィネーションを開発する.
- ベータ・ケト・チオールエステル合成のためのチオールエステルへのC-S挿入を達成するために.
主な方法:
- 主要な中間物質としてイノラートを使用した.
- E選択的オレフィネーションのための特殊な反応条件を開発しました.
- C-S挿入反応機構を調査した.
主要な成果:
- 高いE選択性を持つテトラ置換された機能化されたオレフィンを成功裏に合成しました.
- チオールエステルのC-S挿入で生成されたβ-ケトチオールエステル.
- イノラート中間物質の汎用性を実証しました.
結論:
- 開発された方法論は,貴重なオレフィン化合物への効率的な経路を提供します.
- この研究は,有機合成におけるイノラテの合成的有用性を拡大する.
関連する概念動画
03:00Preparation of Epoxides
Overview
Epoxides result from alkene oxidation, which can be achieved by a) air, b) peroxy acids, c) hypochlorous acids, and d) halohydrin cyclization.
Epoxidation with Peroxy Acids
Epoxidation of alkenes via oxidation with peroxy acids involves the conversion of a carbon–carbon double bond to an epoxide using the oxidizing agent meta-chloroperoxybenzoic acid, commonly known as MCPBA. Since the O–O bond of peroxy acids is very weak, the addition of electrophilic oxygen of peroxy acids to...
Epoxides result from alkene oxidation, which can be achieved by a) air, b) peroxy acids, c) hypochlorous acids, and d) halohydrin cyclization.
Epoxidation with Peroxy Acids
Epoxidation of alkenes via oxidation with peroxy acids involves the conversion of a carbon–carbon double bond to an epoxide using the oxidizing agent meta-chloroperoxybenzoic acid, commonly known as MCPBA. Since the O–O bond of peroxy acids is very weak, the addition of electrophilic oxygen of peroxy acids to...
01:15Carboxylic Acid Derivatives: Overview
Carboxylic acid derivatives are formed by replacing the hydroxyl group of carboxylic acids with a different functional group. The most common carboxylic acid derivatives are:
01:13Esters to Carboxylic Acids: Acid-Catalyzed Hydrolysis
Hydrolysis of esters under acidic conditions proceeds through a nucleophilic acyl substitution. In the presence of excess water, the reaction proceeds in a reversible manner, forming carboxylic acids and alcohols.
During hydrolysis, the ester is first activated towards nucleophilic attack through the protonation of the carboxyl oxygen atom by the acid catalyst. The protonation makes the ester carbonyl carbon more electrophilic. In the next step, water acts as a nucleophile and adds to the...
During hydrolysis, the ester is first activated towards nucleophilic attack through the protonation of the carboxyl oxygen atom by the acid catalyst. The protonation makes the ester carbonyl carbon more electrophilic. In the next step, water acts as a nucleophile and adds to the...
01:27Aldol Condensation with β-Diesters: Knoevenagel Condensation
The Knoevenagel condensation is an aldol-type reaction involving the condensation of aldehydes or ketones with active methylene compounds such as β-diesters to produce substituted olefins.
01:07Alkylation of β-Ketoester Enolates: Acetoacetic Ester Synthesis
Acetoacetic ester synthesis is a method to obtain ketones from alkyl halides and β-keto esters. The reaction occurs in the presence of an alkoxide base that abstracts the acidic proton of the β-keto esters. The step results in an enolate ion which is doubly stabilized. The enolate then reacts with an alkyl halide via the SN2 process to produce an alkylated ester intermediate with a new C–C bond. The hydrolysis of the intermediate, followed by acidification, results in an alkylated β-keto acid.
01:14Alkylation of β-Diester Enolates: Malonic Ester Synthesis
Malonic ester synthesis is a method to obtain α substituted carboxylic acids from ꞵ-diesters such as diethyl malonate and alkyl halides.