每周分子 | Molecule of the Week

Original ACS 美国化学会 ACS美国化学会 2023-03-12

收录于合集 #每周分子 142个

点击上方， 订阅话题 ，不错过每周分子！

每周分子：二甲醚

Molecule of the Week: Dimethyl ether

二甲醚(DME)又称甲醚，是最简单的脂肪醚。二甲醚是一种无色气体。二甲醚目前主要由甲醇脱水来生产制备；不过，研究人员们也正在着眼于利用生物甲烷或从纤维素或木质素中获取的生物质进行二甲醚的可持续性生产。

二甲醚主要用于制备其他小分子，如醋酸或硫酸二甲酯。它也是一种喷雾罐推进剂和替代氯氟烃的制冷剂。二甲醚被认为是一种比碳氢化合物更清洁的燃料。

二甲醚除了存在于地球上，最近的一项重大发现报道了其也存在于外太空。今年3月，荷兰莱顿大学(Leiden University)的研究人员借助阿塔卡马大型毫米/亚毫米波阵列望远镜(ALMA)，于距离地球444光年的蛇夫座(Ophiuchus)行星形成盘中发现了二甲醚。二甲醚包含9个原子，是迄今为止在太空中观测到的最大分子。

一些天体生物学家一直乐观地推测，二甲醚的存在可能是“外太空”存在生命的迹象。

二甲醚信息速览

CAS 登记号	115-10-6
CAS SciFinder命名	Methane,1,1′-oxybis-
分子式	C₂H₆O
摩尔质量	46.07 g/mol
外观	无色气体
沸点	–25 °C
水溶性	71g/L (STP)^a

二甲醚危害信息

GHS分类：易燃气体，分类1
H220-极易燃气体
GHS分类：加压气体，液化气
H280-含加压气体，加热可能爆炸
GHS分类：特定性靶器官毒性，单次暴露；麻醉作用，分类1
H336-可引起嗜睡或头晕
GHS分类：单纯窒息剂，分类1
可替代氧气，引起迅速窒息

【关于每周分子】

自2001年以来，“每周分子”已成为广受欢迎的栏目。多数分子由读者推荐。每个结构都经由科学家审查，并以3-D和平面图像的形式显示，同时附有该分子简介。可以通过美国化学文摘社 (CAS) 提供的CAS SciFinderⁿ中的CAS REGISTRY获取“每周分子”的更多信息。CAS REGISTRY中的每条物质信息都展示了物质的CAS登记号、索引名、通用名、商品名、书目信息等其他更多信息。发送邮件至motw@acs.org推荐您感兴趣的分子吧。

Dimethyl ether (DME), a colorless gas, is the simplest aliphatic ether. Also called methyl ether, it is currently produced by dehydrating methanol; but researchers have an eye on it for sustainable production from biogenic methane or biomass derived from cellulose or lignin.

DME is primarily used to make other small molecules such as acetic acid or dimethyl sulfate. It is also a spray-can propellant and a refrigerant to replace chlorofluorocarbons. It has been proposed as a cleaner-burning fuel than hydrocarbons.

Far beyond its terrestrial presence, DME was a significant recent discovery in outer space. In March, researchers at Leiden University (the Netherlands) used the Atacama Large Millimeter/submillimeter Array telescope to identify the molecule in a planet-forming disc in the constellation Ophiuchus, 444 light-years from Earth. With nine atoms, DME is the largest molecule yet observed in space.

Sertraline continues to be a frequently prescribed antidepressant. But its success has come with an environmental cost: This year, a review by South African scientists Lawrence Mzukisi Madikizela* and Somandla Ncubeb cited dozens of drugs, including sertraline, that have been detected in marine organisms and seafood. This finding is a major concern for ocean life because of the aquatic toxicity statements shown in the hazard information table.

Always optimistic, some astrobiologists have speculated that the presence of DME could be an indicator of life “out there”.

Dimethyl ether fast facts

CAS Reg. No.	115-10-6
SciFinder nomenclature	Methane, 1,1′-oxybis-
Empirical formula	C₂H₆O
Molar mass	46.07 g/mol
Appearance	Colorless gas
Boiling point	–25 °C
Watersolubility	71 g/L (STP)^a

Dimethyl etherhazard information

Flammable gases, category 1
H220-Extremely flammable gas
Gases under pressure, liquefied gas
H280-Contains gas under pressure; may explode if heated
Specific target organ toxicity, single exposure; narcotic effects, category 3
H336-May cause drowsiness or dizziness
Simple asphyxiant, category 1
May displace oxygen and cause rapid suffocation

About Molecule of the Week

MOTW has been a popular feature on ACS website since 2001. Many molecules are suggested by our website visitors. Every structure is reviewed by a scientist and displayed in 3-D and flat images with a brief description. Each week’s molecule also links to a sample record from the CAS REGISTRY, which is searched using CAS SciFinderⁿ. Each record displays the registry number, index name and synonyms, bibliographic information, and more. Send us a molecule suggestion at motw@acs.org.

往期回顾：

每周分子Molecule of the Week：舍曲林

每周分子Molecule of the Week：N，N﹣二乙基间甲苯甲酰胺

每周分子Molecule of the Week：佛手柑素

每周分子Molecule of the Week：无穷烯

每周分子Molecule of the Week：克林霉素

每周分子Molecule of the Week：羟基马桑毒素

每周分子Molecule of the Week：甲酸

每周分子Molecule of the Week：三氯吡氧乙酸

每周分子Molecule of the Week：柠檬酸

每周分子Molecule of the Week：八甲基环四硅氧烷

每周分子Molecule of the Week：胍丁胺