电喷雾质谱法对两种六钼酸盐的芳香亚胺含氯衍生物的结构研究  

Study onthe Structure of Two Chlorinated Aromatic Imines Derivatives of Hexamolybdate by ESI-MS

作　　者：赵莹莹 史晓敏 王倩倩 Zhao Yingying;Shi Xiaomin;Wang Qianqian(Fenyang College of Shanxi Medical University,Fenyang,Shanxi 032200,China;School of Chinese Language and Literature,Shanxi Normal University,Taiyuan,Shanxi 030031,China)

机构地区：[1]山西医科大学汾阳学院,山西汾阳032200 [2]山西师范大学文学院,山西太原030031

出　　处：《化学世界》2024年第5期312-317,共6页Chemical World

基　　金：山西省高等学校科技创新(No.2023L485);山西医科大学汾阳学院引进人才启动基金(No.2022A05);山西医科大学汾阳学院引进人才启动基金(No.2022A09)资助项目。

摘　　要：采用二环己基碳二亚胺(DCC)法,合成了两种具有不同取代基位置的六钼酸盐芳香亚胺含氯衍生物TBA_(2)[Mo_(6)O_(18)(N-C_(6)H_(4)-Cl-p)](I)(TBA为四丁基胺)和TBA_(2)[Mo_(6)O_(18)(N-C_(6)H_(4)-Cl-o)](II),用电喷雾电离质谱法(ESI-MS)对两种衍生物进行了质谱一级谱(MS)表征及碰撞诱导解离(CID)气相裂解反应研究。MS结果表明,两种衍生物在溶液中的存在形式主要为裸多阴离子[Mo_(6)O_(18)(N-C_(6)H_(4)-Cl)]^(2-)及少量H^(+)、TBA^(+)单电荷加合阴离子簇[HMo_(6)O_(18)(N-C_(6)H_(4)-Cl)]^(-)和[(TBA)Mo_(6)O_(18)(N-C_(6)H_(4)-Cl)]^(-);CID研究结果表明两种衍生物在N_(2)碰撞下发生无机多酸骨架中Mo-O键碎裂,形成包含有机组分芳香亚胺的低核数的多钼酸根离子及相应低核数的多钼酸根离子,这些子离子进一步碎裂形成更低核数的新一代子离子(二级质谱(MS/MS)图);化合物II的子离子中包含芳香亚胺的多钼酸根子离子丰度比化合物I更低,是由于化合物II离子中Mo≡N的稳定性低于化合物I导致的,这与其最佳碰撞能量值(CE)更小相一致。建立了化合物I和II的ESI-MS指纹图谱,使该类衍生物的结构表征信息更加全面。Two chlorinated aromatic imine derivatives of hexamolybdate,TBA_(2)[Mo_(6)O_(18)(N-C_(6)H_(4)-Cl-p)](TBA=Tetrabutylamine)(I)and TBA_(2)[Mo_(6)O_(18)(N-C_(6)H_(4)-Cl-o)](II)were synthesized and characterized using electrospray ionization mass spectrometry(ESI-MS)via the collision induced dissociation(CID)gas phase cracking pathway.ESI-MS results showed that the main existence form of two derivatives in solution are bare polyanion[Mo_(6)O_(18)~(N-C_(6)H_(4)-Cl)]^(2-)and a small number of single charge addition anion clusters of[HMo_(6)O_(18)(N-C_(6)H_(4)-Cl)]^(-)and[(TBA)Mo_(6)O_(18)(N-C_(6)H_(4)-Cl)]^(-)by H^(+)and TBA^(+).The CID results indicated that the multiple Mo--O bonds on polyoxometalate(POM)framework were broken to generate low nuclearity molybdate fragments that retain the organic component under N_(2)collision,while the corresponding low-nuclearity molybdate fragment was also generated at the same time so that these daughter ions were further broken to form a new generation of daughter ions with lower nuclear numbers(secondarymass spectrometry(MS/MS)diagram).The abundance of daughter ions containing organic component aromatic imine compoundIIis lower than that of imine compoundI,due to the lower stability of Mo≡Nincompound II ions,which is consistent with its optimal collision energy being less than compoundI.This study established ESI-MS fingerprints of compounds IandII,further expanding the structural characterization library of these organic functionalized polyoxometalates.

关 键 词：电喷雾电离质谱法 六钼酸盐的芳香亚胺衍生物 碰撞诱导解离(CID) 指纹图谱 

分 类 号：O611.5[理学—无机化学]