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The preparation and structural characterization of tin(IV) complexes supported by (2,2'-phenylphosphino)bis(4,6-di-tert-butylphenolate) ([OPO]2-) are described. The reaction of in-situ prepared Li2[OPO] with SnCl4 in THF at -35 degrees C produced [OPO]SnCl2(THF) as a THF adduct. Addition of SnCl4 to a THF solution of H2[OPO] in the presence of 2 equiv of NEt3 at room temperature led to the formation of the "ate" complex {[OPO]SnCl3}(HNEt3). The metathetical reactions of Li2[OPO] with R2SnCl2 (R=Me, n-Bu) in THF at -35 degrees C generated the corresponding five-coordinate dialkyl complexes [OPO]SnR2. In addition to the multinuclear NMR spectroscopic data for all new compounds, X-ray structures of [OPO]SnCl2(THF), [OPO]SnMe2, and [OPO]Sn(n-Bu)2 are presented.

The synthesis and structural characterization of a series of homo- and heteropolynuclear clusters constructed with a potentially tetradentate phosphine triphenolate ligand are presented. Treatment of tris(3,5-di-tert-butyl-2-hydroxyphenyl)phosphine (H3[O3P]) with 3 equiv of nBuLi in diethyl ether at -35 °C affords hexanuclear Li6[O3P]2(OEt2)2 (1) as colorless crystals. In situ lithiation of H3[O3P] with 3 equiv of nBuLi in THF at -35 °C followed by metathetical reactions with MnCl2 or NiCl2(DME) gives crystals of forest green pentanuclear MnLi4[O3P]2(THF)3 (2) or dark brown tetranuclear Ni2Li2[O3P]2(THF)2 (3), respectively. Alkane elimination of ZnR2 (R = Me, Et) with H3[O3P] in THF at 25 °C generates high yields of colorless crystalline trinuclear Zn3[O3P]2(THF)2 (4). The cluster structures of 1-4 were all determined by single crystal X-ray diffraction studies. These molecules represent the first examples of metal complexes supported by phosphine triphenolate derivatives. The cluster 2 contains a paramagnetic core of high spin Mn(II) (S = 5/2) as indicated by solution and solid state magnetic susceptibility measurements.

Segmental bony defects of the mandible constitute a complete loss of the regional part of the mandible. Although several types of customized three-dimension-printed mandible prostheses (CMPs) have been developed, this technique has yet to be widely used. We used CMP with a pressure-reducing device (PRD) to investigate its clinical applicability. First, we used the finite element analysis (FEA). We designed four models of CMP (P1 to P4), and the result showed that CMP with posterior PRD deployment (P4 group) had the maximum total deformation in the protrusion and right excursion positions, and in clenching and left excursion positions, posterior screws had the minimum von Mises stress. Second, the P4 CMP-PRD was produced using LaserCUSING from titanium alloy (Ti-6Al-4V). The fracture test result revealed that the maximum static pressure that could be withstood was 189 N, and a fatigue test was conducted for 5,000,000 cycles. Third, animal study was conducted on five male 4-month-old Lanyu pigs. Four animals completed the experiment. Two animals had CMP exposure in the oral cavity, but there was no significant inflammation, and one animal had a rear wing fracture. According to a CT scan, the lingual cortex of the mandible crawled along the CMP surface, and a bony front-to-back connection was noted in one animal. A histological examination indicated that CMP was significantly less reactive than control materials ( p = 0.0170 ). Adequate PRD deployment in CMP may solve a challenge associated with CMP, thus promoting its use in clinical practice.