Yates, C. G. published the artcileNew intermediates and dyes. X. Preparation and reactions of 2-n-alkylquinizarins, SDS of cas: 2642-37-7, the publication is Journal of the Chemical Society (1965), 626-9, database is CAplus.
2-Methylquinizarin was prepared by hydrolysis of 4-chloro-l-hydroxy-2 methylanthraquinone, or better, from 1,4-diamino-2-methylanthraquinone and aqueous alk. dithionite. 2-Propyl-, 2-butyl-, 2- hexyl-, 2-heptyl-, and 2-octylquinizarin were derived by the interaction of leucoquinizarin and an aliphatic aldehyde: this reaction appeared to be limited, as the use of decyl- and dodecylaldehyde gave quinizarin only. Inhibiting effects of the 2-n-alkyl groups in reactions with amines were examined Thus, 2-methyl-, propyl-, and butylquinizarin and aqueous NH3 gave some disubstitution of the hydroxy groups, but with derivatives of longer alkyl chain, only monosubstitution occurred; MeNH2 afforded yellow fluorescent products, probably formed by loss of water from 2-alkyl-1,4-bis(methylamino)anthraquinones. Whereas cyclohexylamine gave excellent yields of 2-alkyl-1,4-bis(cyclohexylamino)anthraquinones, disubstitution was inhibited in reactions with PhNH2, which gave monoanilino derivatives
Journal of the Chemical Society published new progress about 2642-37-7. 2642-37-7 belongs to indole-building-block, auxiliary class Indole,Salt,Sulfonate,Inhibitor,Inhibitor, name is Potassium 1H-indol-3-yl sulfate, and the molecular formula is C9H9ClN2, SDS of cas: 2642-37-7.
Referemce:
https://www.nature.com/articles/s41429-020-0333-2,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles