Reactions of diethylamine and ethylene catalyzed by Pt II or Pt 0 : transalkylation vs. hydroamination

Pavel Dub (1) , Aurélien Béthegnies (1) , Rinaldo Poli (1)

1 LCC - Laboratoire de chimie de coordination

PtBr2/nBu4PBr (without solvent) or K2PtCl4/NaBr (in water), previously shown to efficiently catalyze the hydroamination of ethylene by aniline, are poor catalysts for the hydroamination of ethylene by diethylamine. A DFT study on the hydroamination mechanism indicates that the energetic span of the C2H4/Et2NH catalytic cycle is close to that of the C2H4/PhNH2 cycle. The poor performance is attributed to rapid catalyst degradation with reduction to metallic platinum. The produced Pt 0 , on the other hand, catalyzes a transalkylation process, partially transforming Et2NH into Et3N, EtNH2, and NH3. The latter process is inhibited by C2H4. Mechanistic considerations on the Pt 0catalyzed transalkylation process are presented.

Mots clés: Platinum; Ethylene hydroamination; Amine transalkylation; DFT calculations; Aqueous catalysis

Domaines: Catalyse; Chimie organique; Chimie théorique et/ou physique

Pavel Dub, Aurélien Béthegnies, Rinaldo Poli. Reactions of diethylamine and ethylene catalyzed by Pt II or Pt 0 : transalkylation vs. hydroamination. European Journal of Inorganic Chemistry, 2011, 2011 (33), pp.5167-5172. ⟨10.1002/ejic.201100624⟩. ⟨hal-03157864⟩