Oxone-Promoted Cyclization/Hydrolysis of 1,5-Enenitriles Initiated via Direct C(sp3)–H Oxidative Functionalization: Access to Pyrrolidine-2,4-diones

Abstract

A novel method for assembling pyrrolidine-2,4-diones from 1,5-enenitriles and acetone/acetonitrile via a cyclization/hydrolysis has been established under metal catalyst- and base-free conditions, with Oxone as a green oxidant and H2O as an additive at 90-110 ℃. This strategy is highlighted by cyclization/hydrolysis of alkyl cyanides, achieving direct C(sp3)–H oxidative functionalization, and giving full conversion of the substrates with excellent functional group compatibility.

FeIII‐Based Eutectic Mixtures as Multi‐task and Reusable Reaction Media for Efficient and Selective Conversion of Alkynes into Carbonyl Compounds

“…In the same line, the presence of fluorine in ortho ‐position of the aromatic ring in the terminal alkyne 1 p requires the employment of 80 °C as reaction temperature (entry 17, Table 2). However, and as previously reported by Cai and co‐workers, [32] the simple translocation of the fluoride substituent into the para position of the aromatic ring allows decreasing the reaction temperature down to 45 °C (entry 18, Table 2). Nevertheless, the presence of a nitrile or ester group in the starting alkyne ( 1 r , s , entries 19–20, Table 2) requires to increase: i) both the temperature (80 °C) and the reaction time (48 h) for 1 r (entry 19); or i i) the reaction time for 1 s (72 h, entry 20) to obtain only low to moderate yields of the desired methyl ketones 2 r , s .…”