Diaminodicyanoquinones: Fluorescent Dyes with High Dipole Moments and Electron‐Acceptor Properties

Fluorescent dyes are applied in various fields of research, including solar cells and light‐emitting devices, and as reporters for assays and bioimaging studies. Fluorescent dyes with an added high dipole moment pave the way to nonlinear optics and polarity sensitivity. Redox activity makes it possible to switch the molecule's photophysical properties. Diaminodicyanoquinone derivatives possess high dipole moments, yet only low fluorescence quantum yields, and have therefore been neglected as fluorescent dyes. Here we investigate the fluorescence properties of diaminodicyanoquinones using a combined theoretical and experimental approach and derive molecules with a fluorescence quantum yield exceeding 90 %. The diaminodicyanoquinone core moiety provides chemical versatility and can be integrated into novel molecular architectures with unique photophysical features.     

Structure elucidation of phase II metabolites by tandem mass spectrometry: an overview

The present paper provides a summary of the collision-induced dissociation of protonated and deprotonated phase II metabolites of drugs and pesticides. This overview is based on published literature and unpublished data from the authors. In particular, glutathione conjugates and their biotransformation products are discussed in detail. In addition, the fragmentation of the major classes of conjugates, i.e. glucuronides, glucosides, malonylglucosides, sulfates, acetates, methyl and glycine conjugates, is reported. Collision-induced dissociation, as studied by tandem mass spectrometry, allows the rapid identification of the type of conjugate, whereas the exact conjugation site can in general be determined only by additional NMR experiments.     

Metallsubstituierte Phosphaalkene und Acylphosphane. 31. Zur Reaktivität von (η5-C5Me5)(CO)2FeP = C(NMe2)2 gegenüber Zinndichlorid. Röntgenstrukturanalyse von {(η5-C5Me5)[η1-(Me2N)2C = P?P = C(NMe2)2](CO)2Fe}+{[Me2N)2C]2P}+(FeCl4)2−

Transition-Metal Substituted Phosphaalkenes and Acyl Phosphanes. 31 [1] Reactivity of (η⁵-C₅Me₅)(CO)₂FeP = C(NMe₂)₂ towards Tin Dichloride. X-Ray Structure Analysis of {(η⁵-C₅Me₅)[η¹-(Me₂N)₂C = P? P = C(NMe₂)₂](CO)₂Fe}⁺{[Me₂N)₂C]₂P}⁺(FeCl₄)^2? Reaction of metallophosphaalkene (η⁵-C₅Me₅)(CO)₂ · FeP = C(NMe₂)₂ ( 1 ) with anhydrous tin dichloride affords the salt-like compound {(η⁵-C₅Me₅)[η¹-(Me₂N)₂C = P? P = C(NMe₂)₂] · (CO)₂Fe}⁺{[(Me₂N)₂C]₂P}⁺(FeCl₄)^2? 5 which is characterized by single crystal X-ray analysis and spectra (IR, ¹H, ³¹P-NMR).