Disodium 4,4'-dinitrostilbene-2,2'-disulfonate

Disodium 4,4'-dinitrostilbene-2,2'-disulfonate

Identifiers
CAS Number	3709-43-1
Properties
Chemical formula	C14H8N2Na2O10S2
Molar mass	474.335
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Disodium 4,4′-dinitrostilbene-2,2′-disulfonate is an organic compound with the formula (O₂NC₆H₃(SO₃Na)CH)₂ This salt is a common precursor to a variety of textile dyes.

Preparation and reactions

In the laboratory disodium 4,4′-dinitrostilbene-2,2′-disulfonate is obtained by sulfonation of 4-nitrotoluene giving the intermediate product, which is further oxidized with sodium hypochlorite yielding 4,4′-dinitrostilbene-2,2′-disulfonic acid disodium salt.^[1]

The compound is useful because it couples with aniline derivatives to give azo dyes. Commercially important dyes derived from this compound include Direct Red 76, Direct Brown 78, and Direct Orange 40.^[2]

References

1. "Synthesis of disodium 4,4′-dinitrostilbene-2,2′-disulfonate". www.PrepChem.com.
2. Klaus Hunger, Peter Mischke, Wolfgang Rieper, Roderich Raue, Klaus Kunde, Aloys Engel "Azo Dyes" in Ullmann’s Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH, Weinheim.doi:10.1002/14356007.a03_245.