The coordination around the Sb atom in the title compound, (C(6)H(16)N)[Sb(C(14)H(10)O(3))(2)], is fourfold in a pseudo-trigonal-bipyramidal pattern in which one of the equatorial sites is occupied by the stereoactive lone pair of electrons. The four ligating atoms comprise the hydoxylate and carboxyl-ate O atoms from two independent benzilate ligands, each of which forms a five-membered chelat...

Here we present detailed structural data on the effect of high pressure on Cu-btc. Application of pressure causes solvent to be squeezed into the pores until a phase transition occurs, driven by the sudden compression and expansion of equatorial and axial Cu-O bonds.

In the title compound, C(12)H(13)ClO(4), the 1,3-dioxane ring adopts a chair conformation and the 2-chloro-benzene and methyl substituents occupy equatorial sites. The carboxyl group is in an axial inclination. In the crystal, carb-oxy-lic acid inversion dimers linked by pairs of O-H⋯O hydrogen bonds generate R(2) (2)(8) loops.

The synthesis of the CD spiroketal fragment of spongistatin 1 (altohyrtin A) has been accomplished utilizing the addition of a metalated pyrone to an aldehyde and subsequent acid-catalyzed spirocyclization. A stereoselective hydrogenation and subsequent conformational inversion establish the C19 stereocenter and the axial-equatorial spiroketal center.

OBJECTIVE To compare, in terms of their demonstration of tears of the anterior glenoid labrum, oblique axial MR arthrography obtained with the patient's shoulder in the abduction and external rotation (ABER) position, with conventional axial MR arthrography obtained with the patient's arm in the neutral position. MATERIALS AND METHODS MR arthrography of the shoulder, including additional obli...

The intertropical convergence zone (ITCZ) migrates north–south on seasonal and longer time scales. Previous studies have shown that the zonal-mean ITCZ displacement off the equator is negatively correlated with the energy flux across the equator; when the ITCZ lies in the Northern Hemisphere, energy flows southward across the equator, and vice versa. The hemisphere that exports energy across th...

In the title polymeric coordination compound, [Sn(CH(3))(3)(C(6)H(5)O(2)Se)](n), the Sn(IV) atom has a distorted trigonal-bipyramidal geometry, with two O atoms of two symmetry-related bridging phenyl-seleninate anions in axial positions and three methyl groups in equatorial positions. In the crystal, the complex exhibits a chain structure parallel to the b axis.

The Sn atom in the title compound, [Sn(CH(3))(2)(C(13)H(10)NO(2))(2)], has a highly distorted octa-hedral coordination with the equatorial plane made up of four O atoms from two N-benzoyl-N-phenyl-hydroxy-laminate ligands and the axial positions occupied by two methyl groups. The crystal structure is stabilized by van der Waals inter-actions.

In previous studies, it was reported that a neighbouring equatorial ester group is essential for a good yield of nitrite-mediated triflate inversion, whereas with neighbouring benzyl ether groups or axial ester groups, mixtures are generally produced. In the present study, the origin of this difference was addressed. The ambident reactivity of the nitrite ion has been found to be the cause of t...

Density functional theory (DFT) calculations are presented on biomimetic model complexes of cysteine dioxygenase and focus on the effect of axial and equatorial ligand placement. Recent studies by one of us [Y. M. Badiei, M. A. Siegler and D. P. Goldberg, J. Am. Chem. Soc. 2011, 133, 1274] gave evidence of a nonheme iron biomimetic model of cysteine dioxygenase using an i-propyl-bis(imino)pyrid...