関連する実験動画
Updated: May 28, 2026

09:56
Hierarchical and Programmable One-Pot Oligosaccharide Synthesis
Published on: September 6, 2019
ドナー-受容体-安定化シリコンアナログの酸アンヒドリド
Rajendra S Ghadwal1, Ramachandran Azhakar, Herbert W Roesky
1Institut für Anorganische Chemie, Georg-August-Universität Göttingen, Tammannstrasse 4, 37077 Göttingen, Germany. rghadwal@uni-goettingen.de
Journal of the American Chemical Society
|October 18, 2011
まとめ
研究者は,ユニークなOSi-O-SiOコアを特徴とする酸アンヒドリドの安定したシリコンアナログを合成しました. この新しい化合物は,様々なスペクトロスコピーおよび結晶学的方法を使用して特徴づけられ,その構造と安定性を確認しました.
科学分野:
- オーガノシリコン化学 化学
- メイングループ 化学
- 超分子化学 超分子化学
背景:
- 酸アンヒドリドは,有機合成における重要な機能群である.
- 反応性種の安定したシリコンアナログには大きな関心があります.
- ボラン添加物は,反応性中間物質の安定化に使用されます.
研究 の 目的:
- 酸アンヒドリドの安定したシリコンアナログを合成し,特徴づけること.
- OSi-O-SiOコアの構造および電子特性を調査する.
- シリコン化合物の安定化におけるボラン添加物の有用性を調査する.
主な方法:
- モノクロロシリレンと,N-ヘテロサイクリックカルベン (NHC) の存在における水-ボラン添加物との反応.
- 元素解析と多核核核磁気共振光譜による特徴化.
- 単結晶X線 difraktionとDFT計算による構造的決定.
主要な成果:
- 酸性アンヒドリドの安定したシリコンアナログの合成に成功した化合物 4.
- OSi-O-SiOのコア構造の確認. OSi-O-SiOのコア構造の確認. OSi-O-SiOのコア構造の確認. OSi-O-SiOのコア構造の確認. OSi-O-SiOのコア構造の確認. OSi-O-SiOのコア構造の確認. OSi-O-SiOのコア構造の確認.
- 実験データと計算データは,提案された構造と安定性を支持しています.
結論:
- 酸性アンヒドリドの新しい,安定したシリコンアナログが準備されています.
- OSi-O-SiOコアは,大量の置換物質とボラン添加物によって安定化されています.
- この研究は,シリコン化学の範囲を拡大し,反応性中間安定化に関する洞察を提供します.
関連する概念動画
Reactions of Acid Anhydrides
The reactions of acid anhydrides are analogous to the reactions of acid chlorides and proceed via a nucleophilic acyl substitution. They only differ in the identity of the leaving group. During an acid chloride reaction, the leaving group is a chloride ion, and the by-product is hydrochloric acid. However, in an acid anhydride reaction, the leaving group is a carboxylate ion, and the by-product is a carboxylic acid.
Preparation of Acid Anhydrides
One of the methods for preparing symmetrical or unsymmetrical acid anhydrides involves the treatment of acid chlorides with the sodium salt of carboxylic acids. The reaction proceeds via a nucleophilic acyl substitution.
The carboxylate ion acts as a nucleophile that attacks the carbonyl carbon of the acid chloride to form a tetrahedral intermediate. Subsequently, the re-formation of the carbonyl group with the loss of the chloride ion as a leaving group leads to the formation of an acid...
The carboxylate ion acts as a nucleophile that attacks the carbonyl carbon of the acid chloride to form a tetrahedral intermediate. Subsequently, the re-formation of the carbonyl group with the loss of the chloride ion as a leaving group leads to the formation of an acid...
Alkylation 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.
Acidity of 1-Alkynes
The acidic strength of hydrocarbons follows the order: Alkynes > Alkenes > Alkanes. The strength of an acid is commonly expressed in units of pKa — the lower the pKa, the stronger the acid. Among the hydrocarbons, terminal alkynes have lower pKa values and are, therefore, more acidic. For example, the pKa values for ethane, ethene, and acetylene are 51, 44, and 25, respectively, as shown here.
Nomenclature of Carboxylic Acid Derivatives: Acid Halides, Esters, and Acid Anhydrides
Naming Acid Halides
The IUPAC and common names of acid halides are derived from the corresponding carboxylic acids, by changing “ic acid” to “yl halide.” For example, as shown below, the IUPAC name ethanoyl chloride is derived from ethanoic acid, and the common name, acetyl chloride, is obtained from acetic acid.
The IUPAC and common names of acid halides are derived from the corresponding carboxylic acids, by changing “ic acid” to “yl halide.” For example, as shown below, the IUPAC name ethanoyl chloride is derived from ethanoic acid, and the common name, acetyl chloride, is obtained from acetic acid.
Structures of Carboxylic Acid Derivatives
Structure of Carboxylic Acid Derivatives
Carboxylic acid derivatives contain an acyl group attached to a heteroatom such as chlorine, oxygen, or nitrogen. The carbonyl carbon and oxygen are both sp2-hybridized with an unhybridized p orbital.
The three sp2 orbitals of the carbonyl carbon form three σ bonds, one each with the carbonyl oxygen, the α carbon, and the heteroatom, whereas the other two sp2 orbitals of the carbonyl oxygen are occupied by the lone pairs. Further, the unhybridized p...
Carboxylic acid derivatives contain an acyl group attached to a heteroatom such as chlorine, oxygen, or nitrogen. The carbonyl carbon and oxygen are both sp2-hybridized with an unhybridized p orbital.
The three sp2 orbitals of the carbonyl carbon form three σ bonds, one each with the carbonyl oxygen, the α carbon, and the heteroatom, whereas the other two sp2 orbitals of the carbonyl oxygen are occupied by the lone pairs. Further, the unhybridized p...

