Structural characteristics of hazardous organic matter (1)

A large proportion of accidents in the practice of organic synthesis originate from dangerous goods

Hazardous organic compounds are abbreviated as hazardous organics.

Structure determines performance is the basic law of chemistry.

The dangerous nature of hazardous organics is that they contain one or more unstable chemical centers, which are also called chemically active centers or chemically active sites, and are generally composed of chemically active groups

1) Explosive group

There are about dozens of high-sensitivity "explosive groups" in dangerous organic substances commonly used in organic synthesis laboratories

2) Very reactive groups

If there are multiple highly reactive groups in the molecule, coupled with appropriate conditions (temperature, pH, impurity catalyst, light, etc.

3) Toxic group

Toxic groups include strongly corrosive strongly acidic or strongly basic groups, aromatic heterocyclic halogenated compounds that cause sensitization, and compounds whose active positions are substituted by halogens (a-position halogen-substituted or allylic halogen-substituted compounds) , smelly group and the like

4) Other functional groups

Other functional groups include potential gas generating groups, groups (or structures) that may generate peroxides, radioactive elements in compounds, DNA methylating agents, and so on

Case 1

A R&D team carried out a kilogram scale amplification reaction based on the mature process conditions provided by the customer and on the basis of many successful experiences at the level of tens of grams to 100 grams:

Put 1.

Figure 26-2 Screenshot of the accident video

(a) Before explosion: (b) Detonation: (c) Immediately after explosion

Reason analysis: It may be that oxone reacts with acetone to generate peroxyacetone

In the second beating process with endoketone, the excess potassium hydrogen persulfate composite salt had to react with acetone, plus long-term stirring and full contact to produce part of peroxyacetone, which decomposed and exploded during the concentration process

In addition, this is an amplified dangerous reaction, and the risk factor increases greatly with the increase in the number of reaction materials.

Although the reaction was subjected to the DSC analysis of A and B (reaction substrate and product) before the kilogram scale amplification, and the safety assessment was carried out with this data, the detection and analysis were not comprehensive.

Related links: Design of synthetic route and judgment of reaction risk (2)