1,2-Dichlorobenzene
chemical compound

1,2-Dichlorobenzene, or orthodichlorobenzene (ODCB), is an aryl chloride and isomer of dichlorobenzene with the formula C6H4Cl2. This colourless liquid is poorly soluble in water but miscible with most organic solvents. It is a derivative of benzene, substituted with two adjacent chlorine atoms.
It is mainly used as a precursor chemical in the synthesis of agrochemicals, as a preferred solvent for dissolving and working with fullerenes, as an insecticide, and in softening and removing carbon-based contamination on metal surfaces.
Production and uses
1,2-Dichlorobenzene is obtained as a side-product of the production of chlorobenzene:
C6H5Cl + Cl2 → C6H4Cl2 + HCl
The reaction also affords the 1,4- and small amounts of the 1,3-isomer. The 1,4- isomer is preferred over the 1,2- isomer due to steric hindrance. The 1,3- isomer is uncommon because it is a meta- compound, while chlorine, like all halogens, is an ortho/para- director in terms of electrophilic aromatic substitution.
It is mainly used as a precursor to 1,2-dichloro-4-nitrobenzene, an intermediate in the synthesis of agrochemicals. In terms of niche applications, 1,2-dichlorobenzene is a versatile, high-boiling solvent. It is a preferred solvent for dissolving and working with fullerenes.
“1,2-Dichlorobenzene” enters the record as chemical compound. Crown Archives preserves that source wording while asking what 2-Dichlorobenzene, chemical and compound can confirm, complicate or overturn.
Why this record matters
“1,2-Dichlorobenzene” is worth following because a concise public description often conceals a longer documentary argument. Here, 2-Dichlorobenzene, chemical and compound provides the most credible route into that argument.
The date and method of observation matter as much as the stated conclusion, especially where classification or consensus has changed. The source revision retrieved here is dated Aug 20, 2026. The linked authority identifier is Q2609815. None of the 0 selected statements returned an explicit reference.
Scientific names, classifications and consensus can change while older terminology persists in catalogues and historical literature. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Check terminology, classification and the date of the cited evidence. Scientific names and technical consensus can change while older records retain historical value.
- Current terminology
- Classification context
- Finding cited technical literature
Primary datasets, specimen catalogues, standards bodies and the most recent peer-reviewed literature.
Three-step research path
- Establish the record: confirm the title “1,2-Dichlorobenzene”, its source revision and the description used here.
- Expand the search: follow 1,2-Dichlorobenzene primary sources, 1,2-Dichlorobenzene archive and 2-Dichlorobenzene research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “1,2-Dichlorobenzene”?
- Is the terminology current, historical or disputed?
- Has classification or technical consensus changed since the cited source?
Search terms from this dossier
This entry incorporates text from “1,2-Dichlorobenzene” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.