On the alcoholysis of alkyl-aluminum (iii) alkoxy-NHC derivatives: reactivity of the Al-carbene Lewis pair versus Al-alkyl

Vincent Dardun (1) , Léon Escomel (1) , Erwann Jeanneau (2) , Clément Camp (1)

1 C2P2 - Laboratoire de Chimie, Catalyse, Polymères et Procédés, R 5265
2 UCBL - Université Claude Bernard Lyon 1

The reaction of a bifunctional hydroxy N-heterocyclic carbene (NHC-OH)ligand with alkyl-aluminum(III) derivatives appears to be dependent of the precursor used.The expectedalkoxy-NHC metallated productis indeed obtained with Al(iBu)3. In contrast, the sterically hindered[Al(iBu)(OAr)2] (OAr = 2,6-di-tertbutyl-4-methylphenoxy) displays reactivity at the carbeneand affords an imidazolium-aluminate zwitterion. The non-innocence of the Al-NHC motif is further highlighted by the heterolytic cleavageof the phenol O-H bond across the Al-CNHCbondfrom Al(O-NHC)X2derivatives (X = iBu, OAr).

Domaines: Chimie

Vincent Dardun, Léon Escomel, Erwann Jeanneau, Clément Camp. On the alcoholysis of alkyl-aluminum (iii) alkoxy-NHC derivatives: reactivity of the Al-carbene Lewis pair versus Al-alkyl. Dalton Transactions, 2018, 47 (31), pp.10429--10433. ⟨10.1039/C8DT01498A⟩. ⟨hal-01877466⟩