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Developing practical and mild strategies for the direct functionalization of white phosphorus (P4) without chlorination is an appealing but formidable challenge. To this end, we report a breakthrough in the preparation of structurally diverse dialkylphosphines and trialkylphosphines that rely on the successive generation of carbon‐centered radicals from N‐hydroxyphthalimide (NHPI) esters and the controllable alkylation of the P4 molecule under transition‐metal‐ and photocatalyst‐free conditions. To facilitate separation and prevent product losses during purification, the corresponding oxidation products dialkylphosphine oxides (DAPOs) and trialkylphosphine oxides (TAPOs) were isolated. This photoinduced phosphorylation reaction features one‐pot operation, high product selectivity, and tolerates a broad range of alkyl NHPI esters, including derivatives of complex natural products and pharmaceuticals. Further diversified transformation of DAPOs to construct P−F, P−C, P−N, and P−O bonds was also demonstrated.

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The present study investigates a new solvent system for the dissolution of chitosan and a new method for preparing chitosan membranes. First, aqueous tartaric acid was used to pretreat chitosan. Then, the chitosan was precipitated with ethanol or other regenerating agents, and 1.5 mL of 1-ethyl-3methylimidazolium acetate ([EMIM]AC) was added to obtain translucent suspensions. The chitosan membranes were prepared by casting the suspensions on glass plates and allowing solvent evaporation.The structure and properties of the films were investigated by SEM, FT-IR, XRD and TGA. Also, the mechanical properties, as well as physical and chemical characteristics, of the chitosan films were evaluated. The results indicated that the optimum dissolution time was 10 min and the most suitable drying temperature was 60 C. The thus-prepared film was moderately thick (about 0.02 mm) and had a smooth surface, without curling. The chitosan film prepared by ethanol regeneration had a tensile strength of up to 24 MPa, a minimum swelling degree of 78%, and a water vapor transmission rate of 270 g m À2 d À1 without the addition of plasticizer. View Article Online a Calculated from the Mark-Houwink equation: [h] ¼ KM a The molecular weight of chitosan M ¼ 398300.This journal is