1,2-dimethoxyethane brief introduction

乙二醇二甲醚（Dimethoxyethane），也称作1,2-二甲氧基乙烷，俗称“二甲基溶纤剂”。无色透明液体，略有乙醚气味，溶于水、乙醇、乙醚和氯仿。化学性质稳定，可用作硝酸纤维素、树脂、寡糖和多糖的溶剂。他的沸点高于乙醚和THF，所以常被用来当作那两种的替代品。另外它可以与双齿配体反应成螯合物，因此常被用在有机金属化学反应中，例如：格林纳试剂、还原氢化反应和铃木反应、施蒂勒反应等钯催化偶联反应。乙二醇二甲醚的间位交叉式是最低能量、最稳定的构象，而不是它的对位交叉式构象。

1,2-dimethoxyethane Basic information

1,2-dimethoxyethane Numbering system

1,2-dimethoxyethane Physical and Chemical Properties

Appearance and characteristics:

Water white liquid

Density:

0.867 g/mL at 25 °C(lit.)

Boiling point:

85 °C(lit.)

Melting point:

-69 °C

Flash point:

32 °F

Refractive index:

n20/D 1.379(lit.)

Water solubility:

Miscible

Stability:

Stable, but explosive peroxides may form on exposure to air. Test for the presence of peroxides before heating. Avoid heat, light, air. Highly flammable. Store under inert gas.

Storage conditions:

The warehouse is ventilated, low-temperature and dry, and stored separately from oxidants

Steam density:

3.1 (20 °C, vs air)

Steam pressure:

187mmHg at 25°C

security information

• RTECS：

• KI1451000

Safety instructions:

S53-S45

Hazard category code:

R11; R19; R20; R60; R61

WGK Germany：

one

Dangerous goods transportation code:

UN 2252 3/PG 2

Customs code:

twenty-nine million ninety-one thousand and nine hundred

Hazard category:

three

Packaging grade:

II

Dangerous goods signs:

F

Supplementary Hazard Statement:

May generate explosive peroxides.

Hazard prevention instructions:

P201; P210; P280; P308 + P313; P370 + P378; P403 + P235

Signal words:

Danger

Danger signs:

GHS02, GHS07, GHS08

Hazard description:

H225; H315; H360FD

Production method and purpose

Production method

1. Composed of ethylene glycol monomethyl ether and metallic sodium; Obtained through the reaction of chloromethane. Reflux ethylene glycol monomethyl ether with metallic sodium until the metallic sodium reacts completely, cool down to 45 ℃, and introduce chloromethane. After the reaction is complete, perform distillation and collect the 84-85.5 ℃ fraction to obtain the finished product. Refining method: The testing method for peroxides is the same as that for ether. Peroxides can be refluxed together with stannous chloride or removed through activated alumina. Then add a small amount of metallic sodium to remove trace amounts of moisture. Other refining methods include first drying with sodium wire and then distilling with lithium aluminum hydride under nitrogen flow. Alternatively, it can be dried with anhydrous calcium chloride for several days, filtered, distilled with metallic sodium, or stored with lithium aluminum hydride and distilled before use.

2. While stirring, add a small amount of metallic sodium to ethylene glycol monomethyl ether at 60 ℃, controlling the temperature at 78-81 ℃. After adding metallic sodium, cool it down to 45 ℃, and then introduce chloromethane. The reaction equation is: after the reaction is complete, distill and collect the 84.5-85.5 ℃ fraction to obtain ethylene glycol dimethyl ether.

3. After drying with sodium wire, add lithium aluminum hydride for distillation in the presence of nitrogen. Alternatively, dry with anhydrous calcium chloride for several days, filter out the calcium chloride, and then add metallic sodium for distillation. Alternatively, add lithium aluminum hydride and let it stand for distillation.

use to

It is mainly used in the fields of polymer chemistry, electrochemistry, and boron chemistry processes, as well as in organic synthesis solvents such as resins and nitrocellulose.

toxicity