概括
默奇森石有机聚合物在氧化后产生甲基基酸,与产生基衍生物的陆地聚合物不同. 这表明外星人的起源可能来自太阳星云中的费舍尔-托普施反应.
科学领域:
- 天体化学是天体化学.
- 有机地化学 有机地化学
- 宇宙化学 宇宙化学
背景情况:
- 石,如默奇森C2石,含有复杂的有机物质.
- 了解外星有机分子的起源和组成对于天体生物学至关重要.
- 陆地有机聚合物,如素和酸,提供了比较的参考.
研究的目的:
- 为了分析默奇森石中的有机聚合物.
- 为了识别从石的有机聚合物中提取的化合物.
- 为了比较石聚合物的氧化产品与陆地同类.
主要方法:
- 使用性铜氧化物氧化Murchison石的有机聚合物.
- 由此产生的酸和非酸有机酸的识别和表征.
- 获得的化合物与来自陆地聚合物氧化的化合物进行比较.
主要成果:
- 鉴定了七种酸,特别是甲基 (3-基) 酸和3-基-1,5-基-二糖酸.
- 酸被推断是源于聚合物中的乙烯.
- 在相同的条件下,陆地聚合物产生了主要的偏基衍生物.
结论:
- 甲基基酸结构表明穆奇森聚合物的外星起源.
- 聚合物中的乙烯可能是通过太阳星云中的CO和H2的Fischer-Tropsch类反应形成的.
- 这一发现区分了外星有机物与地球上的聚合物,如木质素和酸.
相关概念视频
Olefin Metathesis Polymerization: Overview
Recently, the development of olefin metathesis polymerization advanced the field of polymer synthesis. Simply put, the reorganization of substituents on their double bonds between two olefins in the presence of a catalyst is known as the olefin metathesis reaction. The use of metathesis reaction for polymer synthesis is called olefin metathesis polymerization.
Ruthenium-based Grubbs catalyst is the most commonly used catalyst for olefin metathesis polymerization. Grubbs catalyst consists of a...
Ruthenium-based Grubbs catalyst is the most commonly used catalyst for olefin metathesis polymerization. Grubbs catalyst consists of a...
Ethers from Alkenes: Alcohol Addition and Alkoxymercuration-Demercuration
Overview
Ethers can also be prepared from alkenes through acid-catalyzed addition of alcohols and alkoxymercuration–demercuration.
Preparation of Ethers by Acid-Catalyzed Addition of Alcohol to Alkenes
The acid-catalyzed addition of alcohol to an alkene involves treating the alkene with an excess of alcohol in the presence of an acid catalyst to form an ether under suitable conditions. The hydrogen will add to the less substituted carbon so that the nucleophile can attack the more substituted...
Ethers can also be prepared from alkenes through acid-catalyzed addition of alcohols and alkoxymercuration–demercuration.
Preparation of Ethers by Acid-Catalyzed Addition of Alcohol to Alkenes
The acid-catalyzed addition of alcohol to an alkene involves treating the alkene with an excess of alcohol in the presence of an acid catalyst to form an ether under suitable conditions. The hydrogen will add to the less substituted carbon so that the nucleophile can attack the more substituted...
Structure and Nomenclature of Ethers
Structure and Bonding
Ethers are organic compounds with an ether functional group which is characterized by an oxygen atom connected to two — identical or different — alkyl, aryl, or vinyl groups. The C–O–C linkage in dimethyl ether — the simplest ether — has an approximately tetrahedral bond angle of 110.3 degrees. The oxygen atom is sp3- hybridized, with the C–O distance being about 140 pm.
Classification of Ethers
Based on their attached substituent groups, ethers can be classified into two...
Ethers are organic compounds with an ether functional group which is characterized by an oxygen atom connected to two — identical or different — alkyl, aryl, or vinyl groups. The C–O–C linkage in dimethyl ether — the simplest ether — has an approximately tetrahedral bond angle of 110.3 degrees. The oxygen atom is sp3- hybridized, with the C–O distance being about 140 pm.
Classification of Ethers
Based on their attached substituent groups, ethers can be classified into two...
Olefin Metathesis Polymerization: Acyclic Diene Metathesis (ADMET)
Acyclic diene metathesis polymerization or ADMET polymerization involves cross-metathesis of terminal dienes, such as 1,8-nonadiene, to give linear unsaturated polymer and ethylene. As ADMET is a reversible process, the formed ethylene gas must be removed from the reaction mixture to complete the polymerization process.
Similar to cross-metathesis, ADMET also involves the formation of metallacyclobutane intermediate by [2+2] cycloaddition of one of the double bonds of a terminal diene with...
Similar to cross-metathesis, ADMET also involves the formation of metallacyclobutane intermediate by [2+2] cycloaddition of one of the double bonds of a terminal diene with...
Autoxidation of Ethers to Peroxides and Hydroperoxides
Ethers represent a class of chemical compounds that become more dangerous with prolonged storage because they tend to form explosive peroxides when standing in the air. Autoxidation is the spontaneous oxidation of a compound in air. In the presence of oxygen, ethers slowly oxidize to form hydroperoxides and dialkyl peroxides.
Ethers to Alkyl Halides: Acidic Cleavage
Ethers are generally unreactive and unsuitable for direct nucleophilic substitution reactions since the alkoxy groups are strong bases and, therefore, poor leaving groups. However, ethers readily undergo acidic-cleavage reactions. Ethers can be converted to alkyl halides when heated with strong acids such as HBr and HI in a sequence of two substitution reactions.


