Synthesis, characterisation and functionalisation of BAB-type dual-responsive nanocarriers for targeted drug delivery: evolution of nanoparticles based on 2-vinylpyridine and diethyl vinylphosphonate

Defined, stable nanoparticles were synthesised from block copolymers generated via REM-GTP and functionalised with folic acid.

Synthesis of diethyl 2-{[3-(triethoxysilyl)propyl]amino}ethylphosphonate

Diethyl 2-{[3-(triethoxysilyl)propyl]amino}ethylphosphonate is promising reagent for the modification of silica surface and thus for the creation of chelate adsorbents for extraction of d‑metals ions from water media. Diethyl 2-{[3-(triethoxysilyl)propyl]amino}ethylphosphonate was synthe­sized by alkylation of 3-aminopropyltriethoxysilane (APTES) with diethyl vinylphosphonate under quick neat heating. The possible alternative approaches to the synthesis of this compound were investigated (alkylation of APTES and N-acetylAPTES) as well as behavior of APTES towards heating in absolute ethanol and THF. APTES was shown to be not stable in absolute ethanol, that is caused by polycondensation processes. Because of this fact, previously reported protocol of diethyl 2‑{[3‑(triethoxysilyl)propyl]amino}ethylphosphonate synthesis in ethanol turned to be impossible.

Catalyst-free Diels–Alder reactions of vinylphosphonates with cyclopentadienones

The unprecedented thermal Diels–Alder reaction of the diethyl vinylphosphonate and diethyl styrylphosphonate with various cyclopentadienones is described. In these Diels–Alder reactions, catalysis was not required and the corresponding cycloadducts derivatives were obtained. The tetraethyl vinylidene-1,1-bis-phosphonate was found to be less reactive than monophosphonates with the same cyclopentadienones.