New, air-stable inorganic soft materials are accessible under mild conditions via TEMPO-mediated radical hydrophosphination of alkenes using polyphosphinoboranes.

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High molar mass polyphosphinoboranes substituted with an alkyl group at phosphorus [RPH−BH 2 ] n (R = tBu, 1-Ad, iPr, Cy, nHex, and Me) have been successfully prepared via dehydropolymerization of the phosphine−boranes RPH 2 •BH 3 using an iron precatalyst, [CpFe(CO) 2 (OTf)] (100 °C, toluene, 2.0 M, 10−100 h). Substrate purity and the reaction conditions were found to be crucial in obtaining a high molar mass material as the major product (M n = 18,200−57,200 g mol −1 and D̵ = 1.24− 3.40). For example, the addition of small quantities of primary phosphines, a potential monomer contaminant, was found to lead to a lower molar mass oligomeric material [RPH−BH 2 ] x . Our experiments indicated that the added Lewis basic primary phosphine does not induce main-chain scission post-polymerization. In contrast, a phosphine-mediated termination process during the catalytic cycle appears to compete with the polymerization of the phosphine−borane monomer. The resulting poly(alkylphosphinoboranes) were characterized by multinuclear NMR spectroscopy, gel permeation chromatography, and electrospray ionization mass spectrometry. The thermal properties were also investigated by thermogravimetric analysis, which showed the materials to be stable to weight loss up to 100−120 °C, and differential scanning calorimetry, which revealed strongly side group-dependent T g values that ranged from −76 to 87 °C.

Aims To evaluate the efficacy and safety of ultra‐rapid lispro (URLi) versus lispro in a paediatric population with type 1 diabetes (T1D) in a Phase 3, treat‐to‐target study. Materials and Methods After a 4‐week lead‐in to optimize basal insulin, participants were randomized to double‐blind URLi (n = 280) or lispro (n = 298) injected 0 to 2 minutes prior to meals (mealtime), or open‐label URLi (n = 138) injected up to 20 minutes after start of meals (postmeal). Participants remained on pre‐study basal insulin (degludec, detemir or glargine). The primary endpoint was glycated haemoglobin (HbA1c) change from baseline after 26 weeks (noninferiority margin 4.4 mmol/mol [0.4%]). Results Both mealtime and postmeal URLi demonstrated noninferiority to lispro for HbA1c: estimated treatment difference (ETD) for mealtime URLi −0.23 mmol/mol (95% confidence interval [CI] −1.84, 1.39) and postmeal URLi −0.17 mmol/mol (95% CI −2.15, 1.81). Mealtime URLi reduced 1‐hour postprandial glucose (PPG) daily mean (P = 0.001) and premeal to 1 hour postmeal PPG excursion daily mean (P < 0.001) versus lispro. The rate and incidence of severe, nocturnal or documented hypoglycaemia (<3.0 mmol/L [54 mg/dL]) were similar for all treatments. With mealtime URLi versus lispro, the rate of postdose hypoglycaemia (<3.0 mmol/L) was higher at ≤2 hours (P = 0.034). The incidence of treatment‐emergent adverse events was similar for all treatments. More participants reported an injection site reaction with mealtime URLi (7.9%) versus postmeal URLi (2.9%) and lispro (2.7%). Conclusions In children and adolescents with T1D, URLi demonstrated good glycaemic control, and noninferiority to lispro in HbA1c change for mealtime and postmeal URLi. When dosed at the beginning of meals, URLi reduced 1‐hour PPG and PPG excursions versus lispro.