Mild N-Alkylation of Amines with Alcohols Catalyzed by the Acetate Ru(OAc)2 (CO)(DiPPF) Complex

Rosario Figliolia; Salvatore Baldino; Hans G Nedden; Antonio Zanotti-Gerosa; Walter Baratta

doi:10.1002/chem.201702996

Mild N-Alkylation of Amines with Alcohols Catalyzed by the Acetate Ru(OAc)₂ (CO)(DiPPF) Complex

Chemistry. 2017 Oct 17;23(58):14416-14419. doi: 10.1002/chem.201702996. Epub 2017 Sep 19.

Authors

Rosario Figliolia¹, Salvatore Baldino¹, Hans G Nedden², Antonio Zanotti-Gerosa², Walter Baratta¹

Affiliations

¹ Dipartimento DI4A, Università di Udine, Via Cotonificio 108, 33100, Udine, Italy.
² Johnson Matthey Fine Chemicals Division, 28 Cambridge Science Park, Milton Road, Cambridge, CB4 0FP, UK.

PMID: 28857344
DOI: 10.1002/chem.201702996

Abstract

The acetate complex Ru(OAc)₂ (DiPPF) (2) obtained from Ru(OAc)₂ (PPh₃ )₂ (1) and 1,1'-bis(diisopropylphosphino)ferrocene (DiPPF) reacts cleanly with formaldehyde affording Ru(OAc)₂ (CO)(DiPPF) (3) in high yield. The monocarbonyl complex 3 (0.4-2 mol %) efficiently catalyzes the N-alkylation of primary and secondary alkyl and aromatic amines using primary alcohols ROH (R=Et, nPr, nBu, PhCH₂ ) under mild reaction conditions (30-100 °C) with an alcohol/amine molar ratio of 10-100. Formation of the monohydride RuH(OAc)(CO)(DiPPF) (4) has been observed by reaction of 3 with iPrOH in the presence of NEt₃ at RT through an equilibrium reaction.

Keywords: N-alkylation; alcohols; amines; borrowing hydrogen; ruthenium.