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Research was conducted to examine the circular dichroism and circular dichroism of anisotropic samples of cisoid enone chromophores. A proposed modification of published rules connecting signs of the n-pi* and band II Cotton effects with enone chirality is presented. Results suggest an interpretation of the breakdown of the helicity rule for the n-pi* band of 3-beta-diastereoisomer caused by a different variation of the different coordinates.

X-ray structural characterization, Raman spectroscopic measurements and quantum chemical calculations were employed in examining the reactivity and structure of [Mo3-mu3S-(muS2)3]4+ complexes. A significant reduction of the stretch resonance frequency was revealed by the Raman data. Calculations also indicated a substantial electron density release to the cation from the anion for the dimeric S2- derivative manifested by decreased net atomic charges.

The complex (H3N(CH2)6NH3)2(H9O4)(RhCl6)Cl2 was derived from 1,6-diaminohexane and rhodium trichloride in 12 M hydrochloric acid. It was found to have chain-like (H9O4)+ ions in the cavities of a complex organic-inorganic framework constructed from 1,6-diammoniohexane, hexachlororhodate-(3-) and chloride ions. The diammoniohexane ions function as intelligent building blocks because they help in the formation of cavities with exactly the right lengths for the inclusion of (H9O4)+.

The synthesis and reactions of a functionalized fluorinated carbadodecarbonate anion, [[1-[H.sub.2]N-[CB.sub.11][F.sub.11]].sup.-] are studied. The results show that the complex cluster expands due to fluorination.

The microwave-assisted Pd-catalyzed Kumada-type cross-coupling reaction of iodinated carba-closo-dodecaborate anions requires smaller amounts of Grignard reagent and catalyst and results in higher yields in much shorter reaction times in comparison to a reaction with conventional heat transfer. 12-Ph3P-closo-1-CB11H11 was identified as the side product of the cross-coupling reactions that use [PdCl2(PPh3)2]. The inner salt, which is the first example for a {closo-1-CB11} cluster with a B-P bond, was selectively synthesized via a related microwave-assisted cross-coupling protocol and characterized by NMR spectroscopy, elemental analysis, and single-crystal X-ray diffraction. In addition, the crystal structures of the tetraethyl ammonium salts of [12-Ph-closo-1-CB11H11]-, [12-(4-MeOC6H4)-closo-1-CB11H11]-, and [12-(H2C-(Me)CC=C)-closo-1-CB11H11]- are described. [ABSTRACT FROM AUTHOR]

In anhydous hydrogen fluoride, K[1-H2N—CB11H11] is fluorinated with elemental fluorine to produce K[1-H2N— CB11F11]. Under strong alkaline conditions, two fluorine atoms of the [1-H2N—CB11F11]- anion are regioselectively exchanged, yielding the [1-H2N-4,6-(HO)2—CB11F9]- anion via [1-H2N-6-HO—CB11F10]- as an intermediate. Both hydroxyc rborate anions were isolated as [Ph4P]+ salts. All of the species were characterized by IR, Raman, and multi-NMR spectroscopy, thermal analysis (DSC) as well as by mass spectrometry (MALDI). The assignment of the NMR ignals was supported by DFT calculations. Solid-state structures of K[1-H2N—CB11F11], [BzPh3P][1-H2N—CB11F11], [Ph4P][1-H2N-4,6-(HO)2—CB11F9], [Ph4P][1-H2N-6-HO—CB11F10], and [BzPh3P][1-H2N—CB11H11 were determined by single-crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

Presents a study which focused on the chain-like isomer of [H904]+ ions in the cavities of a complex organic-inorganic framework. Statistical data and illustrative materials supporting this study.

Dibrominated bis[1]benzothieno[3,2- b ;2',3'- e ][1,4]thiazines (BBTT) are efficiently synthesized and applied in Suzuki and Buchwald-Hartwig cross-coupling reactions to give access to 3,9-disubstituted BBTT derivatives with extended π-conjugation and enhanced electronic properties. For instance, 3,9-di(hetero)aryl substituted BBTT derivatives surpass their parent congeners phenothiazines with lower oxidation potentials and pronounced yellow to orange-red fluorescence (Φ f ≈ 30-45%). In addition, 3,9-bis(di(hetero)arylamino substituted BBTT possess very high lying HOMO energy ( E HOMO = -4.46 to -4.83 eV), a favorable property of hole transport molecules. A representative X-ray structure analysis reveals that the central BBTT core in these extended π-systems is essentially planarized. Upon protonation of a 3,9-bis(di(hetero)arylamino) substituted BBTT, the absorption color shifts from yellow to deep blue with a concomitant loss of the emission. The optical properties of these novel BBTT derivatives can be plausibly rationalized by time-dependent density functional theory (TD(DFT)) calculations and correlation between experimentally determined oxidation potentials and σ p parameters as well as between photophysical data and the specific substituent parameter σ p - by establishing electronic structure-property relationships.