| 摘要 |
1,191,474. Quinizarin derivatives. GAF CORP. 30 Aug., 1967 [12 Oct., 1966], No. 39600/67. Heading C4P. 2 - Methylene - quinizarins in which the methylene group is connected to an alkyl, aryl or heterocyclic residue are obtained by condensing 1 mole of leucoquinizarin with 1 to 1.5 moles of an aliphatic, aromatic or heterocyclic aldehyde at a temperature in the range from 80‹ to 125‹ C. in the presence of a polar organic solvent in which the leucoquinizarin and said aldehydes are soluble until the condensation is complete. The invention also comprises 2-alkylquinizarins of the formula wherein n is 8 to 17; and the following quinizarins: 2 - (2 - hydroxybenzyl) - quinizarin, 2(2,4- dichlorobenzyl) - quinizarin, 2 - piperonal quinizarin, 2(4 - chlorobenzyl)quinizarin and 2 - (p - anisyl)quinizarin. Examples are given for the preparation of the compounds. They are useful dyestuff intermediates. |
