An easy method for the preparation of 4-acylisoxazoles from C(α),O-dianions of oximes

Several C(α),O-dilithiooximes of aromatic ketones were condensed with aroyl chlorides. The presumed diacyl intermediates were not isolated, and the reaction mixtures containing them were acid-cyclized to give 4-acylisoxazoles in 22–62% yield.     

The Reaction of 4-Hydroperoxy-2,4,6-trimethylcyclohexa-2,5-dienone with Acetaldehyde. Formatino of the Bis(peroxyacetal)

The reaction of 4-hydroperoxy-2,4,6-trimethylcyclohexa-2,5-dienone with acetaldehyde using trimethylsilyl trifluoromethanesulfonate as catalyst gives 1,1′-bis[(1,3,5-trimethyl-4-oxo-2,5-cyclohexadienyl) peroxy]diethyl ether ( 7 ) in 70% yield. The structure of this unusual acetal was determined by X-ray analysis.     

Improved CI formula evaluation: Elimination of the phase determination at the determinant level for arbitrarily coupled CSFs

The amount of work needed to evaluate the matrix elements in a configuration interaction calculation can be very large. This is especially true if the phase associated with bringing determinants into maximum coincidence is evaluated at the determinant level. A method is presented which allows the phase to be determined at the occupation level for arbitrarily coupled configuration state functions.     

Born model repulsive interactions in the alkali halides determined from ultrasonic data

Recent studies of the Born Model of the Li, Na, K and Rb halides using ultrasonic data are summarized. It is shown that, when ultrasonic values of the temperature and pressure derivatives of the bulk modulus are used in the Hildebrand approximation for vibrational terms in the free energy, the stiffness π = ? r²W″_R/rW′_R of the net repulsive interaction, W_R, exhibits a smooth and regular behavior when plotted against nearest neighbor distance, d_o. This contrasts with the erratic behavior of the repulsive stiffnesses when hydrostatic compression data are employed. Numerical values of the ultrasonic W_R and π are given. The experimental stiffnesses compare well in their pattern with a recent comprehensive set of theoretical values (exchange charge model) calculated by Hafemeister and Zahrt. A possible improvement of the theory is pointed out.     

Units of algebraic numberfields

Let K be an algebraic number field with proper subfield k. If K and k have the same number of fundamental units then relations between the units of K and k are obtained.     

Intersection preserving finite embedding theorems for partial quasigroups

Aequationes mathematicae -