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Synthesis, Structure, and Properties of Novel Chain-Substituted and Chiral Trimethine Cyanine Dyes with Indoline End Groups Synthesis and spectroscopic properties of the trimethine cyanine dyes 3, 8a, b, and 13a, b as well as 14a-c with new substitution patterns are described. Constitutions and configurations of 3, 8a, b and 14c have been determined by X-ray analyses (Figures 1, 2, and 6). Dye 3 exists in the previously unknown di-cis (E, E, Z, Z) configuration along the methine chain. Attempts to prepare 3 in a base-catalysed reaction unexpectedly led to the rearranged trimethine cyanine dyes 8a, b with a centre of chirality in one of the indoline end groups. Using this Wagner-Meerwein rearrangement after resolution, the chiral heterocyclic quaternary salts (S)-12a- c have been prepared, from which the optically active trimethine cyanine dyes (S,S)-14a-c have been obtained for the first time. The UV/VIS spectra of 3, 8a and 13a (Figure 7) as well as the CD spectra of 12a and 14a (Figures 3 and 4) are compared and discussed.

Agilent Technologies develop and supply X-ray systems for single-crystal diffraction research, including the SuperNova; a compact, highly reliable and very low maintenance instrument providing X-ray data of the highest quality; and the PX Scanner for testing and characterization of protein crystals in their original crystallization drops (in-situ). The SuperNova and PX Scanner are constantly improving, with recent enhancements including a new range of detectors using an Intelligent Measurement System. The Eos S2, Atlas S2 and Titan S2 detector range employs a smart sensitivity control of the electronic gain and is capable of instantaneously switching its binning modes thus providing unprecedented flexibility in tuning every exposure to provide the highest data quality for a wide range of experiments. We have also developed a completely new micro-focus X-ray source based on Gradient Vacuum technology, with novel filament and target designs. This novel source is an integral part of the new Agilent GV1000 X-ray diffractometer, which has been designed for applications that require even higher brightness of the X-ray beam.

Durch Umsetzung des Trisaldehyd-trisacetals 4 mit 1,3,3-Trimethyl-2-methylenindolin (7) und dessen Tetrafluoroborat 8 werden je nach Reaktionsbedingungen entweder der δ-substituierte Heptamethinium-Cyaninfarbstoff 9 oder der [3.3.3]Decamethinium-Cyaninfarbstoff 10 erhalten. Konfiguration und Konformation beider Polymethinfarbstoffe werden spektroskopisch sowie durch Rontgenstrukturbestimmungen ermittelt. - Der UV/Vis-spektroskopische „Trimethinsprung” trinuclearer, Y-konjugierter, methinyloger Guanidinium-Ionen wird mit dem „Vinylensprung” dinuclearer, linear-konjugierter, vinyloger Amidinium-Ionen verglichen (Tab. 1). Syntheses with Aliphatic Dialdehydes, XXXVII, Synthesis, Structure, and Properties of a [3.3.3.]Decamethinium Cyanine Dye, with Indoline End Groups The reaction of the trisaldehyde trisacetal 4 with 1,3,3-trimethyl-2-methyleneindoline (7) and its tetrafluoroborate 8 yields either the δ-substituted heptamethinium cyanine dye 9 or the [3.3.3]decamethinium cyanine dye 10, depending on the reaction conditions. Configuration and conformation of both polymethine dyes have been determined by means of spectroscopic data as well as by X-ray analyses. – The UV/Vis-spectroscopic

New commensurate phases of (NH4)2ZnCl4 are found at low temperatures using X-ray diffraction. With decreasing temperature the cell dimension c of the pseudo-hexagonal axis changes as c 0, 4c 0, 3.5c 0, 3c 0, where c 0 is the fundamental period of the structure. The super-period 3.5c 0 takes place only in coexistence with the superperiod 4c 0 in the temperature range 272 to 268.3 K. A first-order phase transition from the superstructure with 3.5c 0 to the superstructure with 3c 0 occurs at 268.3 K. Coexistence of two super-periods 4c 0 and 3c 0 takes place between 268.3 K and about 266 K. The temperature-dependence of the lattice parameters and the modulation parameter from 293 K to 113 K are presented.

More detailed X-ray diffraction studies of the phase transitions observed earlier by the authors have made it possible to find for (NH4)2ZnCl4 with decreasing temperature the following sequence of phases (represented by the cell parameter c of the pseudohexagonal axis): I: c o, II: 4c o, III: (3.5c o, 4c o), IV: (3c o, 3.5c o, 4c o), V: (3c o, 4c o), VI: 3c o, c o being the fundamental period of the structure and the coexisting superperiods (in parentheses). A coexistence of two or more superperiods can be described as one---correspondingly longer---superperiod. The modulation parameter, the intensities of selected normal and satellite reflections as well as their peak halfwidths were studied as functions of temperature in the vicinity of the phase transitions.

Nach ESR- und ESCA-spektroskopischen sowie rontgenographischen Befunden liegen die [2.2.2] Heptamethindiium-Cyaninfarbstoffe 1 und 2 in kristalliner Form und wahrscheinlich auch in Losung nicht – wie bislang angenommen – als methinyloge Guanidinium-Ionen 1a und 2a vor, sondern als vinyloge Amidinium-Ionen (γ-substituierte Pentamethincyanin oder Dicarbocyaninfarbstoffe (1b und 2b. Syntheses with Aliphatic Dialdehydes, XXXIX. The Conformation of Trinuclear [2.2.2]Heptamethinediium Cyanine Dyes with Indoline End Groups According to ESR and ESCA spectroscopic measurements as well as X-ray analyses the [2.2.2]-heptamethinediium cyanine dyes 1 and 2 exist in the crystalline state and probably in solution as vinylogous amidinium ions (γ-substituted pentamethine cyanine or dicarbocyanine dyes) 1b and 2a.