2831-60-9Relevant articles and documents
Bernasconi,Gross
, p. 1054 (1974)
Preparation method of 2,4-dinitrophenoxyethanol
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Paragraph 0029; 0030, (2017/08/28)
The invention relates to a preparation method of 2,4-dinitrophenoxyethanol. The preparation method comprises the following steps that 1, condensation reaction is conducted, specifically, 2,4-dinitrochlorobene serves as a raw material, is hydrolyzed in an alkaline aqueous solution with the certain concentration and then is condensed with ethylene oxide to obtain condensation reaction liquid; 2, extraction is conducted, specifically, the reaction liquid is dropwise added into a certain organic solvent, layered, concentrated, cooled and crystallized to obtain a crude 2,4-dinitrophenoxyethanol product; and 3, purification is conducted, specifically, the crude 2,4-dinitrophenoxyethanol product is recrystallized to obtain a refined 2,4-dinitrophenoxyethanol product. The preparation method improves the product quality, and also reduces environmental pollution, thereby making product production to be clean and environmentally friendly and enabling products to be more suitable for mass production
Coupling compounds and hair dyeing compositions containing them
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Page/Page column 10, (2008/06/13)
The present invention refers to compounds of the formula (I) wherein R1 is (C1-C4)-alkyl, (C1-C4)-alkyl which is substituted by hydroxy, (C1-C4)-alkoxy, hydroxy-(C1-C4)-alkoxy, CN, -COOR5, -CON(R5)2 or -N(R5)2 or is phenyl; R2 is hydrogen, methyl or ethyl; R3 is (C1-C4)-alkylsulfonyl, (C1-C4)-alkylsulfonyl which is substituted by hydroxy, halogen, cyano, (C1-C4)-alkoxy or -N(R5)2 or is -SO2-CH=CH2, -SO2N(R5)2 or -PO(OR5)2; R4 is hydrogen, (C2-C4)-alkyl which is substituted by hydroxy, (C1-C4)-alkoxy or hydroxy-(C1-C4)-alkoxy; each of R5, independently is hydrogen, (C1-C4)-alkyl or hydroxy-(C2-C4)-alkyl; whereas R3 is not -NHSO2CH3 if R2 and R4 are both hydrogen and R1 is methyl, as well as hair dye compostions containing them.
