No abstract

Three new Cu-Ln cage complexes bridged by phosphonates and acetates are reported; one--a Cu(24)Dy(8) cage--is a new single molecule magnet (SMM).

Reverse-Keggin ions are reported in which a p-block element (antimony) occupies the twelve vertices of a truncated tetrahedron while a d-block element (manganese or zinc) occupies the tetrahedral central cavity. The exterior of the reverse-Keggins also acts as tridentate ligands to further d-block centers.

The reactions of (PhCH2)2SnCl2, (PhCH2)2SnO·H2O, and (PhCH2)3SnCl with 2 equiv of t-BuP(O)(OH)2 afford the tetranuclear organooxotin cage [(PhCH2)2Sn2O(O2P(OH)-t-Bu)4]2 (4) in good yields. The formation of the half-cage intermediate [(PhCH2)2Sn2O(O2P(OH)-t-Bu)4] (4a) en route to 4 has been detected by 119Sn and 31P NMR. The molecular structure of compound 4 as determined by single-crystal X-ray analysis shows a tetranuclear cage structure containing two Sn−O−Sn motifs connected by bridging [t-BuP(OH)(O)2]- ligands. The solid-state structure of 4 is retained in solution.

Organotin clusters and cages have been synthesized in quantitative yields by using a benign solventless synthetic methodology. Using this method a variety of structural forms, which include the drum, O-capped cluster, tetranuclear oxo cage, discrete, and polymeric compounds, have been synthesized. All these compounds (1-11) have been characterized by spectroscopic and analytical techniques. The new compounds, which include the hexameric drum [n-BuSn-(O)OCOAd] 6 (Ad ) adamantyl) 9, a triorganotin-based discrete structure Ph 3 SnO 2 C-C 6 H 2 -2,4,6-Me 3 (10), and a polymer Ph 3 SnOSO 2 -C 6 H 3 -2,5-Me 2 (11), have been characterized by single-crystal X-ray crystallography. § This paper is dedicated to Prof. R. R. Holmes on the occasion of his 75th birghday.

Tetranuclear lanthanide clusters of composition [Ln 4 (µ 3 -OH) 2 (Ph 2 acac) 10 ] (Ln ϭ Pr, Nd, and Sm) (Ph 2 acac ϭ dibenzoylmethanide) were prepared starting from [LnCl 3 ·(n H 2 O)] (n ϭ 6, 7) with 2.5 equivalents dibenzoylmethane in presence of triethylamine. Single crystals X-ray analyses of compounds 1 -3 revealed that each cluster consists of four lanthanide atoms, two µ 3 -oxygen atoms, and ten Ph 2 acac ligands, which make up the peripheral part , 2782Ϫ2785 of the cluster. Three types of coordination modes (η 2 -, (µ-O)-η 2 -, and µ-O) 2 -η 2 ) are observed for the Ph 2 acac ligation to the metal centers.

The synthesis, structure, magnetic and electronic properties of soluble transition metal phosphonate cages utilizing tritylphosphonic acid (TPA) as ligand are reported.

A novel hexameric organooxotin cage [{(n-BuSn)3(PhO)3O}2{HPO3}4] 1 has been assembled by the reaction of [n-BuSnO(OH)] with (PhO)2P(O)H. The structure of 1 consists of two O-capped Sn3 clusters that are attached to each other by four bridging tripodal [HPO3]2- ligands.