| 摘要 |
1287581 Stilbene derivatives IMPERIAL CHEMICAL INDUSTRIES Ltd 22 Dec 1969 [1 Jan 1969] 61/69 Heading C2C Stilbene derivatives of the formula wherein M is an alkali metal, or an optionally substituted ammonium group; X is a mono- or bis-(hydroxyalkyl) amino, N-alkyl-N-hydroxyalkyl amino, or hydroxyalkylamino-alkyl amino group containing from 2 to 6 carbon atoms and optionally containing further hydroxy groups; Y is one of the groups represented by X or an amino, alkylamino, or dialkylamino group in which each alkyl group contains from 1 to 6 carbon atoms, a cycloalkylamino group, an optionally substituted arylamino group or an N-alkyl-N-arylamino group containing up to 10 carbon atoms, a heterocyclic substituted amino group, or a group derived from a cyclic compound containing a basic NH group by loss of the hydrogen atom, are separated in a concentrated form from an aqueous solution thereof by adding an alkali metal or substituted ammonium salt of a halogen acid or sulphuric acid at 60‹ to 100‹ C. in an amount sufficient to precipitate an oil, and separating the oil from the aqueous solution. The compounds may be used as optical brightening agents. |
