Issue 15, 2002

Synthesis, characterization and thermolysis of phosphinite–borane adducts: investigation of an unusual thermally-induced phenolelimination reaction

Abstract

The synthesis, characterization and thermolytic behavior of a new class of phosphinite–borane adducts containing the bulky 2,4,6-t-Bu3C6H2O (Mes*O) group is reported, including the description of the first example of a primary phosphinite–borane adduct isolable at room temperature (Mes*O)PH2·BH31. Adduct 1 and the phenylated derivative (Mes*O)PhPH·BH33 formed highly cross-linked solids, 7 and 8, when heated to 100 and 140 °C, respectively. Characterization of these solids by solid state and solution NMR spectroscopy suggest that both dehydrocoupling (H2 elimination) and Mes*OH elimination occur simultaneously to give the complex products [(Mes*O)xRPHy–BH(2x + 2y + z)]n (R = H or Ph, x + y + z = 1). The tertiary adduct (Mes*O)Ph2P·BH35 and the phosphite–borane (PhO)3P·BH36 were found to decompose at high temperatures via P–B bond cleavage without formation of the corresponding phenol. These results suggest that the thermally-induced formation of Mes*OH from 1 and 3 occurs via α-elimination from a phosphorus center. Adducts 1, 3, 5 and 6 were also structurally characterized by single-crystal X-ray diffraction.

Graphical abstract: Synthesis, characterization and thermolysis of phosphinite–borane adducts: investigation of an unusual thermally-induced phenol elimination reaction

Supplementary files

Article information

Article type
Paper
Submitted
06 Mar 2002
Accepted
30 May 2002
First published
09 Jul 2002

J. Chem. Soc., Dalton Trans., 2002, 2966-2972

Synthesis, characterization and thermolysis of phosphinite–borane adducts: investigation of an unusual thermally-induced phenol elimination reaction

E. Rivard, A. J. Lough and I. Manners, J. Chem. Soc., Dalton Trans., 2002, 2966 DOI: 10.1039/B202361J

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Spotlight

Advertisements