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An asymmetric binary Margules formulation for excess Gibbs energy, enthalpy, and entropy is adequate to describe the 1 bar halite-sylvite solvus in NaCl-KCl (Thompson and Waldbaum 1969). However, a binary Margules formulation is not adequate to describe excess volumes of single-phase chlorides in P-V-T-X from ambient P-T to ~20 kbar and 700 [degrees]C. Excess volumes across NaCl-KCl increase with temperature, decrease with pressure, and show systematic deficits in the consolute region. These patterns can be explained by the importance of a third component--vacancy defects that relieve the lattice stresses of K-Na size mismatch. New, two-phase observations in P-V-T-X allow delineation of the excess Gibbs energies to high pressures where the excess enthalpies and entropies do not depend on Tat each P, but show significant variation between 1 bar and ~20 kbar. The volume, entropy, and enthalpy of K-Na mixing become more ideal at high pressure. But the solvus expands with pressure because entropy approaches ideality faster than enthalpy and, therefore, Gibbs energy of K-Na mixing becomes less ideal with pressure. The consolute temperature rises about 80 [degrees]C in 17 kbar, with little change in consolute composition. The binary Margules equation of state provides a prediction of the rise of the solvus that is impressively convergent with the new observations. This convergence is especially impressive given the clear inadequacies of the binary excess volume formulation on which the prediction is based.

The chloropnictines [([eta]-[C.sub.5][Me.sub.5].sub.2]AsCl (1), [([eta]-[C.sub.5][Me.sub.5]).sub.2]SbCl (2), and [([eta.]-[C.sub.5][Me.sub.5].sub.2]BiCl (3) have been prepared by treatment of the appropriate element trichloride with Li[C.sub.5][sub.Me.5]. X-ray crystallographic assays establish that in the case of 1, both [C.sub.5][Me.sub.5] rings are attached to As in an [[eta].sup.1]([sigma]) fashion. In 2 and 3, the [C.sub.5][Me.sub.5] rings are [eta] delocalized and feature tri- and pentahapto ring binding, respectively, to the group 15 element. Conversion of 1 and 2 to the salts [As[([eta]-[C.sub.5][Me.sub.5].sub.2]] [Al[Cl.sub.4]] (4) and [Sb[[eta][C.sub.5][Me.sub.5]).sub.2]][Al[Cl.sub.4] (5) was effected by reaction with the stoichiometric quantity of [Al.sub.2][Cl.sub.6]. The X-ray crystal structure of 4 is surprisingly complex and features four independent ion pairs in the asymmetric unit with a variety of hapticities for the [eta]-bonded [C.sub.5][Me.sub.5] rings. The structure of the stibocenium cation of 5 involves bis([eta].sup.4]) attachment of the [eta]-bonded [C.sub.5][Me.sub.5] rings. Key words: main group metallocenes, arsocenium cations, stibocenium cations, group 15 pentamethylcyclopentadienyl chlorides.

The trifluoromethyl group can dramatically influence the properties of organic molecules, thereby increasing their applicability as pharmaceuticals, agrochemicals, or building blocks for organic materials. Despite the importance of this substituent, no general method exists for its installment onto functionalized aromatic substrates. Current methods either require the use of harsh reaction conditions or suffer from a limited substrate scope. Here we report the palladium-catalyzed trifluoromethylation of aryl chlorides under mild conditions, allowing the transformation of a wide range of substrates, including heterocycles, in excellent yields. The process tolerates functional groups such as esters, amides, ethers, acetals, nitriles, and tertiary amines and, therefore, should be applicable to late-stage modifications of advanced intermediates. We have also prepared all the putative intermediates in the catalytic cycle and demonstrated their viability in the process. 10.1126/science.1190524

Research has been conducted on 4-(hetero)aryl-substituted 1-chlorophthalazines. The authors describe the synthesis of these compounds carried out via arene/heteroarene heteroarylation by AlCl (sub)3 -induced C-C bond formation reactions.

Research has been conducted on tri(cyclohexyl)tin chloride. The authors have investigate the effect of temperature on the structure of this chloride, and the change of molecular parameters with temperature.

Research has been conducted on N-(fluoroformyl)imidosulfurous dichloride FC(O)N=SCl (sub)2. Results demonstrate that the gas and liquid spectra of this compound indicate the presence of the conformational mixture in both phases.