4934. Indanthrene

Nomenclature

CAS number: 81-77-6
6,15-Dihydro-5,9,14,18-anthrazinetetrone; N,N′-dihydro-1,2,1′,2′-anthraquinonazine.
C28H14N2O4; mol wt 442.42.
C 76.01%, H 3.19%, N 6.33%, O 14.47%.

Description and references

Vat dye discovered by René Bohn (1901). Prepn: Fierz-David, Blangey, Grundlegende Operationen der Farbenchemie (Vienna, 5th ed., 1943) pp 304-305; Thielert, Bauman, US 2693469 (1954 to Bayer); Sutter, Fioroni, US 2831860 (l958 to Ciba); Kastner, US 3138612 (1964 to Allied Chem.). Structure: Weinstein, Merrit, J. Am. Chem. Soc. 81, 3759 (1959).

Chemical structure

Properties

Blue powder, dec 470-500°. uv max on cellophane film: 278 nm. Practically insol in organic solvents. Sol in concd H2SO4, in dil alkali solns. Indanthrene Blue R, the usual commercial grade, is extremely stable to light and heat, but sensitive to chlorine. A purer grade, which is not as sensitive to chlorine, is sold as Indanthrene Brilliant Blue FF.

Use

Mainly to dye cotton.