Platinum nanoparticles stabilized by imidazolium-based phosphine-decorated Polymer Immobilized Ionic Liquids (PPh 2 -PIIL) catalyze the hydrolytic evolution of hydrogen from sodium borohydride with remarkable efficiency, under mild conditions. The composition of the polymer influences efficiency with the catalyst based on a polyethylene glycol modified imidazolium monomer (PtNP@PPh 2 -PEGPIILS) more active than its N-alkylated counterpart (PtNP@PPh 2 -N-decylPIILS). The maximum initial TOF of 169 moleH 2 .molcat À 1 .min À 1 obtained at 30 °C with a catalyst loading of 0.08 mol% is among the highest to be reported for the aqueous phase hydrolysis of sodium borohydride catalyzed by a PtNP-based system. Kinetic studies revealed that the apparent activation energy (E a ) of 23.9 kJ mol À 1 for the hydrolysis of NaBH 4 catalyzed by PtNP@PPh 2 -PEGPIILS is significantly lower than that of 35.6 kJ mol À 1 for PtNP@PPh 2 -N-decylPIILS. Primary kinetic isotope effects k H /k D of 1.8 and 2.1 obtained with PtNP@PPh 2 -PEGPIILS and PtNP@PPh 2 -N-decylPIILS, respectively, for the hydrolysis with D 2 O support a mechanism involving rate determining oxidative addition or σ-bond metathesis of the OÀ H bond. Catalyst stability and reuse studies showed that PtNP@PPh 2 -PEGPIILS retained 70 % of its activity across five runs; the gradual drop in conversion appears to be due to poisoning of the catalyst by the accumulated metaborate product as well as the increased viscosity of the reaction mixture.

Impregnation of phosphine-decorated styrene-based Polymer Immobilized Ionic Liquid (PPh2-PIIL) with ruthenium (III) trichloride resulted in facile reduction of the ruthenium to afford Ru(II) impregnated phosphine oxide-decorated PIIL (O=PPh2PIIL). The derived...

The iridium-catalyzed C-H borylation of diethyl phenylphosphonate results in nonselective mono and bisborylation to afford a near statistical mixture of 3-, 3,5- and 4-boryl substituted aryl phosphonates whereas 3-substituted aryl phosphonates undergo highly regioselective C-H borylation to afford the corresponding meta-phosphonate substituted arylboronic esters as the sole product; the resulting boronic esters were used as nucleophilic reagents in a subsequent palladium-catalyzed Suzuki–Miyaura cross-coupling to generate a range of biarylmonophosphonates. Gratifyingly, the Suzuki–Miyaura cross-coupling can be conducted without purifying the boronic ester which greatly simplifies the synthetic procedure. Graphical Abstract

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Introduction: Hypertension is one of the top non communicable disease in Saudi Arabia. The prevalence of hypertension was 26.1% in crude terms. For males, the prevalence of hypertension was 28.6%, while for females; the prevalence was significantly lower at 23.9%. Patients' awareness is important in the early diagnosis and treatment of many diseases including hypertension. This study contributes in exploring the awareness of hypertension among Saudis population in Al-Madinah Al-Muonawwara. Objective:To estimate prevalence, awareness, treatment adherence and associated factors of hypertension among Saudi aduly population in Al-Madinah. Methods: Cross-sectional design with multistage cluster stratified sampling was used to include 451 Saudi adults participants in the study. Self administered questionnaire was piloted and used to collect the required data. Data were analyzed using SPSS version 16. Univariate analysis was done and cross tabulation was used to summarize the frequency and percentage of the variables. Chi-square was used as an appropriate statistical test and P≤ 0.05 was used as a statistical significant level. Multiple regression was used to control for confounders and assess the risk factors. Results: 15% of the participants has hypertension. Among those with hypertension 77% (50/65) has good knowledge and awareness of hypertension. Approximately half of the participants had changes their life style, 43% (28/65), and had irregular follow up with their doctors, but one third of them did not adhere to their treatment. After adjustment of the confounding factors, hypertension was increased two times by existing of family history of hypertension and higher level of education (PhD holders), (odds ratio =1.99, 95%CI (1.002, 3.96) and (2.05, 95%CI=1.06, 3.99) respectively. Conclusion: Hypertension prevalence was high in Al-Madinah community. Those with hypertension have good awareness about the disease but one third of them did not adhere to third treatment. A control program of hypertension is of utmost important to be established in Al-Madinah.