Étude mécanistique et structurale des résines R/F

Sol–Gel Synthesis of Microporous Carbon Using Resorcinol and Formaldehyde

“…The weight loss tends to decrease by 20%, especially for temperatures 50 °C and 100 °C and becomes practically constant at 110 °C. 33,34 We note two weight losses for samples E2 and E3 between four and five days after drying at 110 °C (Figs 1c and 1d). This weight loss is mainly due to the desorption of physisorbed water and residual organic precursors.…”

Dual functional profluorescent nitroxides for the detection of reactive oxygen species and inhibition of collagen degradation during reassembly

“…Synthesis of the profluorescent nitroxide probe PN1 is depicted in Scheme 2. Michael addition of nitro compound 1 29 to vinyl ketone 2 30 was performed to afford γ-nitro ketone 3 in 64% yield using Triton B as a base. Reductive cyclization of 3 utilizing zinc powder as a reducing agent provided nitrone 4 in 91% yield.…”

Aza‐Michael Reaction: A Decade Later – Is the Research Over?

“…Traditionally, good results are obtained in the presence of catalytic amount of Lewis acids such as ZrOCl 2 ⋅ 8H 2 O, [56] AlCl 3 /SiO 2 , [57] FeCl 3 / Montmorillonite K 10, [58] TiCl 2 (OTf)/SiO 2 [59] (Table 1, entries 13–16). Finally, the aza‐Michael addition of aniline to 5 a is successfully promoted by N‐heterocyclic carbene, [60] enzyme, [61] ionic liquids [62,63] or phase‐transfer catalyst [64] (Table 1, entries 17–21). When the reaction is performed under the same conditions in various solvents (including water) without a catalyst, the target adduct is isolated in low yields or does not formed at all (Table 1, entries 22–25).…”