Potassium carbonate as a green catalyst for Markovnikov addition of azoles to vinyl acetate in PEG

Abstract

A novel strategy to effect the Markovnikov addition between azoles and vinyl-acetate is described. The main attractive features of this process are a mild base catalyst, recyclability of solvent PEG, excellent yields of products, and easy workup procedure.

Synthesis of a new phosphorylated ethylamine, thereon based phosphonamidates and their application as flame retardants

“…The vinyl group possesses a +M‐effect and thus defines the regioselectivity, so that the Markovnikov product is formed. The same selectivity has been reported previously for the addition of other vinyl group‐containing molecules with the N–H bond of imidazole compounds but also with a P–H bond . Acidic work‐up yielded the hydrochloride 4 , which was used as precursor in further reactions as it is a stable, storable version of an amine.…”

Potassium Carbonate–Mediated Efficient and Convenient Synthesis of 3-Methyl-1-phenylchromeno[4,3-c]pyrazol-4(1H)-ones

“…Therefore, we intended to use 1 equiv of potassium carbonate to examine the substrate scope under optimized EFFICIENT SYNTHESIS OF CHROMENOPYRAZOLES 1917 conditions. As potassium carbonate has gained recognition as favorable environmentally benign alternatives [23,24] and acetone represents class 3 solvent, [25] the present methodology adds to the development of sustainable chemistry. To illustrate the versatility of developed methodology, a variety of phenylhydrazines were used as starting materials, and results are depicted in Table 3.…”

Chemo‐Biological Upcycling of Poly(ethylene terephthalate) to Multifunctional Coating Materials

“…In this study, K 2 CO 3 was selected as a catalyst for PET glycolysis because K 2 CO 3 can catalyze PET glycolysis[ 14a , 14b ] and is commonly used as a buffering agent in biotransformation reactions. [ 14c , 14d , 14e , 14f , 14g , 14h ] A PET glycolysis efficiency of K 2 CO 3 was as high as that of Zn acetate. [14] Reaction time (1–5 h), temperature (180–210 °C), and K 2 CO 3 loading (0.05–0.4 g) were optimized for glycolysis of 5 g PET (Figures 1 b, S1, and S2).…”