An effective protocol for the synthesis enantiomerically pure 4-substituted oxetane-2-ones

Molecular architecture of novel potentially bioactive (co)oligoesters containing pesticide moieties established by electrospray ionization multistage mass spectrometry

“…[ R , S ]‐β‐Butyrolactone (98+%; Sigma‐Aldrich Chemie GmbH, Steinheim, Germany) was distilled under reduced pressure over CaH 2 . (4‐Chloro‐2‐methylphenoxy)acetyloxymethylpropiolactone (MCPA‐CH 2 ‐PL) was synthesized by carbonylation of the respective epoxide under ambient CO pressure . Potassium (4‐chloro‐2‐methylphenoxy)acetate was obtained from the reaction between the corresponding acid and potassium hydroxide (POCH S.A., Gliwice, Poland).…”

“…Herein we report a synthetic approach for the biodegradable release system of bioactive compounds based on anionic homo‐ and copolymerization of β‐substituted β‐lactones containing bioactive moieties selected from pesticides. The β‐substituted β‐lactone was synthesized by carbonylation of the respective epoxide under ambient CO pressure . The ability of these lactones to undergo anionic ring‐opening oligomerization in the presence of anionic initiators has been demonstrated.…”

“…The β-substituted β-lactone was synthesized by carbonylation of the respective epoxide under ambient CO pressure. [23] The ability of these lactones to undergo anionic ring-opening oligomerization in the presence of anionic initiators has been demonstrated. The elaborated release system of pesticides should allow to increase, in a controlled way, the loading of pesticides per polymer chains, in comparison to already reported conjugates obtained via anionic ROP of β-butyrolactone initiated by the salt of selected pesticides.…”

Ring Expansions of Oxiranes and Oxetanes

“…The more challenging 1,2-disubstituted oxirane substrates required pressurized CO conditions, but still far lower than when aluminum was employed as the Lewis acid. In 2013, Jurczak reported that the Coates catalyst can be generated in situ from the corresponding chloride salt by reacting in the presence of Co 2 (CO) 8. With this method, handling oxygen sensitive Na[Co(CO) 4 ] is avoided, and the reaction also proceeds with MTBE as solvent [3].…”

“…This two-step process, which starts by converting the ketone into a chiral spirocyclic mixed heteroatom ketal (N/N, N/O or N/S), results in the formation of useful chiral nitrogen heterocycles. In the presence of a Lewis acid (In(OTf) 3 ) and a nucleophile (TMSCN), the spiro-heterocycle opens up to form an iminium ion and a heteroatom nucleophile, which ring opens the oxetane in an intramolecular fashion. The resulting new heterocyclic iminium ion is then captured by the cyanide nucleophile.…”