Uncatalyzed Formation of Polyaminoboranes from Diisopropylaminoborane and Primary Amines: a Kinetically Controlled Polymerization Reaction

Marc Devillard (1) , Carlos Antonio de Albuquerque Pinheiro (1) , Elsa Caytan (1) , Claire Roiland (1) , Chiara Dinoi (2) , Iker Del rosal (2) , Gilles Alcaraz (1)

1 ISCR - Institut des Sciences Chimiques de Rennes
2 LPCNO - Laboratoire de physique et chimie des nano-objets

Recently, we disclosed the uncatalyzed formation of polyaminoboranes (PABs) from monomeric diisopropylaminoborane ((Pr2N)-Pr-i-BH2) and primary amines (RNH2). Their structure is studied through a detailed multinuclear NMR study and their full spectroscopic characterization is presented revealing that N-alkyl substituted PABs exhibit magnetically non-equivalent methylenic protons in the close vicinity of the BN-backbone. We also performed an in-depth theoretical study of this global chemical process. The mechanism is fully apprehended and the strong influence of the temperature on the outcome of the reaction is unveiled. DFT-calculations clearly show that the formation of the polyaminoboranes (RNH-BH2)(n) results from a kinetically controlled step-growth polymerization reaction that can be globally viewed as a head-to-tail association process of the in situ generated transient monomeric monoalkylamino-borane [RNH-BH2].

Mots clés: aminoboranes; BN compounds; boron; polymerization; Inorganic polymers

Domaines: Chimie; Catalyse

Marc Devillard, Carlos Antonio de Albuquerque Pinheiro, Elsa Caytan, Claire Roiland, Chiara Dinoi, et al.. Uncatalyzed Formation of Polyaminoboranes from Diisopropylaminoborane and Primary Amines: a Kinetically Controlled Polymerization Reaction. Advanced Synthesis and Catalysis, 2021, 363 (9), pp.2417-2426. ⟨10.1002/adsc.202001458⟩. ⟨hal-03127420⟩