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Block copolymer vesicles with diverse functionalities and intrinsic hollow structures have received considerable attention due to their broad applications in biomedical fields, including drug delivery, bioimaging, theranostics, gene therapy, etc. However, efficient preparation of block copolymer vesicles with tunable membrane thicknesses and compositions under mild conditions is still a challenge. Herein, we report an aqueous seeded photoinitiated polymerization-induced self-assembly (photo-PISA) for the precise preparation of block copolymer vesicles at room temperature. By changing the total degree of polymerization (DP) of the hydrophobic block in seeded photo-PISA, one can easily tune the membrane thickness without compromising the morphology of vesicles. Moreover, by adding different comonomers such as hydrophobic monomers, hydrophilic monomers, and cross-linkers into seeded photo-PISA, vesicles with different compositions could be prepared without compromising the morphology and colloidal stability. Polymerization kinetics show that seeded photo-PISA can skip the step of in situ self-assembly with a short homogeneous polymerization stage being observed. To demonstrate potential biological applications, enzymatic nanoreactors were constructed by loading horseradish peroxidase (HRP) inside vesicles via seeded photo-PISA. The enzymatic properties of these nanoreactors could be easily regulated by changing the membrane thickness and hydrophobicity. It is expected that this method can provide a facile platform for the precise preparation of block copolymer vesicles that may find applications in different fields.

The synthesis of sulfochromeno [4,3-b] pyrrolidines is described. Under the catalysis of 20 mol% Brønsted base and using 4Å molecular sieves as HF scavenger, imines derived from salicylaldehydes and diethyl aminomalonate react with ethenesulfonyl fluorides through a tandem [3+2] cyclization-SuFEx click reaction to produce sulfochromeno [4,3-b] pyrrolidines in high yields.

A tandem annulation reaction of allyl ketones and ethenesulfonyl fluoride has been described. Under the catalysis of Brønsted base, vinyl ketones reacted with ethenesulfonyl fluoride through a cascade intermolecular Michael addition-intramolecular SuFEx process to afford γ-alkenylated δ-sultones in good to excellent reaction yields. In this reaction, no additional base was needed, and 4 Å Molecular sieves was used as efficient HF scavenger to restrict the neutralization and deactivation of the Brønsted base catalyst.

Block copolymer polymersomes offer considerable access for applications in a variety of fields; however, the traditional cosolvent self-assembly method can only produce polymersomes at a low solids...