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The synthesis of iridium dodecacarbonyl cluster derivatives Ir 4 (CO) 12 with donor ligand such as amine, phosphites, hydrido and cyclic mono and dioxycarbene, NMR and X-ray characterization and fluxional behavior study in solution at variable temperature is briefly reviewed.

The structure of this tetranuclear iridium cluster featuring a terminal Ir–H bond has been investigated by neutron crystallography using the D19 diffractometer at the Institut Laue Langevin in Grenoble. The structure, which is stabilized by numerous C–H⋯O=C hydrogen bonds, has no π–π stacking. The neutron study described here resolves a difficulty encountered in previous X-ray work where it proved impossible to locate reliably the position of hydrogen in the presence of heavy iridium atoms. Neutron crystallography offers unique advantages for this type of problem and in this case has provided the first reliable value for a terminal Ir–H distance of 1.618(14) Å and an intramolecular H–H contact of 2.40(2) Å.

[Rh4(CO)6(μ-Me2PCH2PMe2)3], the first example of a hexasubstituted derivative of Rh4(CO)12, has a ground state geometry in the solid state and in solution of Cs symmetry with four edge-bridging carbonyls and with each diphosphine ligand bridging one edge of the same Rh3 face. The result is an imbalance of the formal electron count at two rhodium atoms. As observed by 13C- and 31P-NMR, the mobility of the ligands is restricted to one μ-CO ↔ η-CO site exchange which astonishingly does not average dynamically the electron count on all four metal atoms.

A 103Rh, 31P and 13C NMR study of [Rh4(CO)6(μ-PPh2)4] in CD2Cl2 indicates that the strongly bonded, bridging, anionic ligand PPh2− takes part in the site exchange of the carbonyl ligands and is actually mobile about the metallic surface of this cluster compound.

The reaction of the cluster complexes [Pt3(μ-CO)3(PR3)3] (PR3 = PPh3 1, PPh2Bz 2, PCy3 3 and PiPr3 4) with dialkyl acetylenedicarboxylate, R′O2CCCCO2R′ (R′ = CH3 or tBu) have been examined under various conditions. At low temperature the alkyne reacts quantitatively giving the unstable adducts [Pt3(CO)3(PR3)3(μ3-alkyne)]. The stereochemistry of the intermediate [Pt3(CO)3(PPh3)3(μ3-tBuO2CCCCO2tBu)] 5 has been deduced from low temperature 195Pt-{1H}, 31P-{1H} and 13C-{1H} NMR spectra. At higher temperature a fluxional process renders two of the three platinum atoms equivalent on the NMR timescale. At room temperature the alkynes convert the starting clusters 1–4 to the stable dinuclear complexes [Pt2(CO)2(PR3)2(μ-R′O2CCCCO2R′)] (R′ = CH3, PR3 = PPh3 6; R = tBu, PR3 = PPh3 7; PPh2Bz 8; PCy3 9 and PiPr3 10) in which the alkyne coordination has the C–C bond collinear with the Pt–Pt bond (6 and 7) or perpendicular to the Pt–Pt axis (9 and 10). The stereochemistry of these two types of dinuclear complexes has been established by NMR and IR studies and confirmed by X-ray diffraction analyses of 8 and 9.

The reaction of [Ir4(CO)10(μ-(Ph2P)2CH2)] with dried KOH forms [Ir4(CO)10(μ-(Ph2P)2CH)]− which subsequently converts into [Ir4(CO)9(μ3-(Ph2P)2CH)]−, a rare example of an Ir cluster with an Ir–C bond (average 2.274(8) A). The same reaction with the weaker base 1,8-diazobicyclo[5.4.0]undec-7-ene or with K2CO3 in wet CH2Cl2 under CO affords the anion [HIr4(CO)9(μ-(Ph2P)2CH2)]−, a hydride-cluster with an unusually long Ir–H distance (2.08(6) A at 90 K). Intramolecular CO scrambling is observed in CD2Cl2 solution above 200 K, preserving the terminal–axial position of the hydride ligand.

602 Background: About 24% of mRCC are older than 74 yo. S is a well-established first-line therapy for mRCC with a specific toxicity profile requiring a dose reduction in 30% of pts. Actually few data are available in the Literature about its use in patients > 75 yo especially as regards efficacy and cost effectiveness of tailored approaches. Methods: The primary end-point of this prospective single arm study, is to assess if a personalized approach is able to decrease the rate of dose reduction to 8% after the first cycle of S.. 19 pts have been estimated to be necessary to explore this hypothesis. Secondary objectives were the safety, treatment duration (TD) and overall survival (OS). Personalized approach was defined as the starting dose of S choose by the medical oncologist based on performance status (PS ECOG) and number of comorbidities. Results: From 2007 to 201421 pts were enrolled. The median age was 77.9 yrs (IQR 74.1-82.1). Seventy-five % had a clear cell carcinoma, 20% had a metastatic disease at diagnosis and 60% had > 2 sites of metastasis. All pts had PS ECOG ≥ 1 and 50% suffered from > 2 comorbidities. 43% were good, 52% intermediate and 5% poor prognosis by IMDC criteria. 3 pts (14%) started S at 50 mg/d, 9 pts (42%) at 37.5 mg/d and 9 pts (42%) started with 25 mg/d. All pts received S with the 4/2 schedule. The dose reduction after the first cycle was 28%. The reason was always toxicity, but no treatment interruption occurred. No pts starting at 25 mg had dose modification. The main toxicity requiring dose reduction was G3 anemia in 1pt, G3-4 thrombocytopenia in 3 pts and G3 leuconeutropenia in 3 pts . The median TD was 11.9 mos (95%CI, 6.5-17.3). The median OS was 33.3 mos (95%CI, 26.1-40.6). Conclusions: This study shows that a personalized starting dose is not able to decrease the rate of dose reduction at first cycle. Nonetheless a personalized strategy does not affect negatively the OS of elderly pts. Actually in elderly pts a disease stabilization without acute adverse events, could be considered an adequate goal. A well tolerated therapy could also be cost effective because part of health cost, especially for elderly pts, derives from their hospitalization for adverse events. Further data are required.

Study Type - Therapy (case series) Level of Evidence 4. What's known on the subject? and What does the study add? The open simple prostatectomy (OSP) is the 'gold standard' for high-volume prostate adenomas. It shows very good functional results despite its invasiveness. Minimally invasive approaches, e.g. laparoscopy or holmium laser enucleation of the prostate, have been 'tested' but none have proved a substitute for the OSP. The robot-assisted approach provides optimal functional results and is easy to perform for experienced robotic surgeons. Extending the indication of robotics to low-incidence pathologies can take advantage of the opportunity to 'see the procedure' using available information technology, e.g. Youtube™ that presents as an unexpectedly useful tool.• To evaluate the outcome, feasibility and reproducibility of a robot-assisted (RA) approach for simple prostatectomy (SP) in cases of high-volume symptomatic benign prostatic hyperplasia (HVS-BPH).• In all, 35 consecutive patients underwent RASP for HVS-BPH using a previously described technique. • The mean prostate volume on preoperative transrectal ultrasonography was 106.6 mL. • All but two patients (with bladder calculi) had an adenoma volume of65 mL and 27 (77.1%)80 mL. Nine patients (25.7%) had an indwelling catheter. • The mean International Prostate Symptom Score (IPSS) was 28.• The median operative duration was 180 min and the mean hospital stay was 3.17 days. • The mean catheter duration was 7.4 days and discontinuous or continuous catheter irrigation was required in two and seven patients, respectively (25.1%). • In all, 10 patients (28.6%) had practically no blood loss. No patients had a transfusion. • The mean postoperative peak urinary flow was 18.9 mL/s (P0.001), while the mean IPSS was 7 (P0.001). • For costs, while superficially RASP appeared more expensive than open SP (OSP), when considering the higher costs of hospitalisation for OSP, RASP was cheaper. Also, bipolar-TURP costs in patients with large-volume prostates had rather similar costs to RASP.• RASP is a feasible and reproducible procedure with outcome advantages when compared with the open or with other minimally invasive techniques (laser or laparoscopy). As a result, a RA approach is worth considering in cases of high-volume prostate adenomas. • Extending the indication of the RA approach, to the SP, requires firstly that the surgeon be proficient in RA surgery and secondly that as the incidence rate of HVS-BPH is low, the surgeon has had the opportunity to 'see the procedure'.

Bis(mesitylene)vanadium(0), V(mes) 2 , underwent a two-electron redox process in heptane with CF 3 SO 3 H affording the vanadium(II) derivative [V(CF 3 SO 3 ) 2 (CF 3 SO 3 H)], an example of a co-ordination compound containing both the acid and its conjugated base in its composition. The vanadium(0) complex and CF 3 CO 2 H gave a product resulting from a one-electron transfer process, namely [V(mes) 2 ][CF 3 CO 2 ]. This compound, which dissolves unchanged in neat CF 3 CO 2 H–(CF 3 CO) 2 O, evolves to the vanadium(II) derivative [H(thf) n ][V(CF 3 CO 2 ) 3 ] (thf = tetrahydrofuran) by addition of tetrahydrofuran. Deprotonation of the vanadium(II) complexes occurs in the presence of thf or heterocyclic nitrogen bases to form the ionic derivatives [HB][VA 3 ], B = thf or a heterocyclic nitrogen base; A = CF 3 SO 3 or CF 3 CO 2 . The trifluoroacetato derivative [H(thf) n ][V(CF 3 CO 2 ) 3 ] undergoes methylation with CH 2 N 2 to the vanadium(II) ester adduct [V(CF 3 CO 2 ) 2 (CF 3 CO 2 CH 3 )], and is oxidized to the vanadium(III) trifluoroacetato derivatives [V(CF 3 CO 2 ) 3 ] and [V(CF 3 CO 2 ) 2 C 14 H 8 O 2 ] by benzoyl peroxide (or dioxygen) and 9,10-phenanthrenedione, respectively.