Novel nanohybrid materials based on l-leucine on hydrotalcite clays: Asymmetric epoxidation reaction of chalcona

The assembly of biorgano-guest to laminar inorganic solids is of increasing interest to their versatile applications in biotechnology or catalysis. We synthesized two different biohybrid materials based on l-leu into the hydrotalcite rehydrated under ultrasound treatment (HTrus), in which l-leu was immobilized by intercalation or by replacing of hydroxyl ions at the edge sites of HTrus. Separately l-leu and HTrus as catalysts showed very poor activity and lack of enantioselectivity in the epoxidation reaction of α,β-unsaturated ketones such as chalcone. Nevertheless, the catalysts presented high activity and even enantioselectivity towards the trans-(R,S)-epoxide depending on the l-leu location on the nanohybrid catalyst.

Figure optionsDownload high-quality image (95 K)Download as PowerPoint slideHighlights
► Two new methodologies for the synthesis of l-leu/HTrus biohybrid materials.
► l-leu immobilized by intercalation or replacing −OH at the edge sites of HTrus.
► Observed synergistic effect between l-leu and HT of nanohybrids.
► High activity and even ee towards the trans-(R,S)-epoxide in J.-C. epoxidation.
► The catalytic properties depend on the l-leu location on the nanohybrid catalyst.