{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,30]],"date-time":"2026-06-30T16:27:19Z","timestamp":1782836839841,"version":"3.54.5"},"reference-count":44,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2020,1,19]],"date-time":"2020-01-19T00:00:00Z","timestamp":1579392000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The optimization of sustainable protocols for reductive amination has been a lingering challenge in green synthesis. In this context, a comparative study of different metal-loaded cross-linked cyclodextrins (CDs) were examined for the microwave (MW)-assisted reductive amination of aldehydes and ketones using either H2 or formic acid as a hydrogen source. The Pd\/Cu heterogeneous nanocatalyst based on Pd (II) and Cu (I) salts embedded in a \u03b2-CD network was the most efficient in terms of yield and selectivity attained. In addition, the polymeric cross-linking avoided metal leaching, thus enhancing the process sustainability; good yields were realized using benzylamine under H2. These interesting findings were then applied to the MW-assisted one-pot synthesis of secondary amines via a tandem reductive amination of benzaldehyde with nitroaromatics under H2 pressure. The formation of a CuxPdy alloy under reaction conditions was discerned, and a synergic effect due to the cooperation between Cu and Pd has been hypothesized. During the reaction, the system worked as a bifunctional nanocatalyst wherein the Pd sites facilitate the reduction of nitro compounds, while the Cu species promote the subsequent imine hydrogenation affording structurally diverse secondary amines with high yields.<\/jats:p>","DOI":"10.3390\/molecules25020410","type":"journal-article","created":{"date-parts":[[2020,1,21]],"date-time":"2020-01-21T03:04:43Z","timestamp":1579575883000},"page":"410","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Cross-Linked Cyclodextrins Bimetallic Nanocatalysts: Applications in Microwave-Assisted Reductive Aminations"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9602-0310","authenticated-orcid":false,"given":"Emanuela","family":"Calcio Gaudino","sequence":"first","affiliation":[{"name":"Dipartimento di Scienza e Tecnologia del Farmaco and NIS\u2014Centre for Nanostructured Interfaces and Surfaces, University of Turin, Via Giuria 9, 10125 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4001-7152","authenticated-orcid":false,"given":"Elisa","family":"Acciardo","sequence":"additional","affiliation":[{"name":"Dipartimento di Scienza e Tecnologia del Farmaco and NIS\u2014Centre for Nanostructured Interfaces and Surfaces, University of Turin, Via Giuria 9, 10125 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1567-8143","authenticated-orcid":false,"given":"Silvia","family":"Tabasso","sequence":"additional","affiliation":[{"name":"Dipartimento di Chimica, University of Turin, Via P. Giuria 7, 10125 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4427-7939","authenticated-orcid":false,"given":"Maela","family":"Manzoli","sequence":"additional","affiliation":[{"name":"Dipartimento di Scienza e Tecnologia del Farmaco and NIS\u2014Centre for Nanostructured Interfaces and Surfaces, University of Turin, Via Giuria 9, 10125 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7574-7350","authenticated-orcid":false,"given":"Giancarlo","family":"Cravotto","sequence":"additional","affiliation":[{"name":"Dipartimento di Scienza e Tecnologia del Farmaco and NIS\u2014Centre for Nanostructured Interfaces and Surfaces, University of Turin, Via Giuria 9, 10125 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9731-6228","authenticated-orcid":false,"given":"Rajender S.","family":"Varma","sequence":"additional","affiliation":[{"name":"Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacky University, \u0160lechtitel\u016f 27, 783 71 Olomouc, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,1,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Ono, N. 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