title: N,N-Di-iso-propylcarbamato complexes of boron.
abstract: N,N-di- iso-propylcarbamato derivatives of boron(III) have been synthesized from di-iso-propylamine and boron trichloride in the presence of carbon dioxide. With a large excess of amine, a single boron product was obtained, [NH2i)Pr2][B(O2CNiPr2)4], 1, while with a lower excess a mixture of 1 and of the dinuclear derivative [B2(O2CNiPr2)6], 2, was produced. By heating in vacuo at 60 degrees C, solid 1 slowly converted to 2. The transformation was reversible, 2 giving 1 back with di- iso-propylamine under carbon dioxide at atmospheric pressure. The molecular structure of both compounds was established by X-ray diffraction methods. Compound 1 is constituted by ion-pairs where the ammonium cation is hydrogen-bonded to the mononuclear anion. Compound 2 is a dinuclear species with two bridging carbamato ligands. In both derivatives, boron shows tetrahedral coordination. As IR- and 1H NMR spectra of the two species are well differentiated, it is possible to monitor the interconversion of 1 and 2 by both spectroscopic methods.
authors.affiliation: Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Pisa, Italy. belli@dcci.unipi.it
authors.forename: Daniela Belli
authors.initials: DB
authors.lastname: Dell'Amico
authors.forename: Fausto
authors.initials: F
authors.lastname: Calderazzo
authors.forename: Luca
authors.initials: L
authors.lastname: Labella
authors.forename: Fabio
authors.initials: F
authors.lastname: Marchetti