新不对称含膦(胂)酸基变色酸双偶氮衍生物的合成及其与稀土元素显色反应的研究  

Syntheses of new asymmetric bis(arylazo) derivatives of chromotropic acid containing phosphono(arsenazo) and spectrophotometric studies on color reaction with rare earths

作　　者：张华山[1] 黎心懿[1] 

机构地区：[1]武汉大学化学系

出　　处：《化学试剂》1989年第6期327-332,323,共7页Chemical Reagents

基　　金：国家科学基金

摘　　要：通过将各种取代基引至变色酸双偶氮衍生物不含成盐基团一侧的偶氮苯的邻、间或对位上,合成了一系列新的不对称含膦(胂)酸基变色酸双偶氮衍生物。这些化合物是偶氮胂 DBM、偶氮胂DBEO、偶氮氯膦 DBM 和对三氟甲基偶氮氯膦等。单取代的试剂与稀土的配合物具有两个吸收峰,分别在610～620 nm 和660～670 nm,而多取代试剂与稀土配合物的吸收峰是630～645 nm。配合物摩尔吸收系数大于或等于10(?)。The authors have synthesized a number ofnew asymmetric 2,7-bis(arylazo)derivatives ofchromotropic acid by changing the position ofdifferent substituents into o-,m-.or positionto azo linkage of the arylazo structure.Thesecompounds are arsenazo DBM,arsenazo DBEO,chlorophosphonazo DBM,p-trifluoromethylchloro- phosphonazo etc.For syntheses of the reagent,the first step is the preparation of the correspond-ing arylamine diazodate by keeping the temper-ature between-2 to+5℃,the diazonium saltsthen undergo coupling reaction with arsenazo I orchlorophosphonazo I in alkaline media.These water-soluble bis(arylazo) derivativesof chromotropic acid react with rare earths form-ing color complexes in acidic media.The visiblespectra of complexes having one substituent withrare earths show two absorption peaks at 610～620 and 660～670 nm respectively,and for thesewith multisubstituent reagents,the absorptionpeaks are observed in the range of 630～645 nm.The molar absorptivities of the complexes are10~5 l.mol^(-1)·cm^(-1)or above.It can be seen thatarsenazo DBM,p-trifluoromethylchlorophosphon-azo etc are highly sensitive and excellent rea-gents for determining the rare earths.ArsenazoDBM is an excellent color reagent for ceriumgroup.It is used to determine microgramamounts of rare earths in steel and alloys.

关 键 词：偶氮胂 偶氮氯膦 稀土 显色反应 

分 类 号：O627.5[理学—有机化学]