CC BY-NC-ND 4.0 · Synthesis 2023; 55(06): 927-933
DOI: 10.1055/a-1902-5592
special topic
Synthetic Advancements Enabled by Phosphorus Redox Chemistry

Catalytic Hydrophosphination of Allenes Using an Iron(II) β-Diketiminate Complex

Callum R. Woof
,
Thomas G. Linford-Wood
,
Mary F. Mahon
,
The Engineering and Physical Sciences Research Council (EPSRC) and the EPSRC Centre for Doctoral Training in Catalysis (Ph.D. studentships awarded to C.R.W. and T.G.L.-W.) are thanked for funding.


Abstract

A rare study into the catalytic hydrophosphination of allenes is reported. Employing an Fe(II) β-diketiminate pre-catalyst, the reaction of HPPh2 proceeds with a range of aryl- and alkylallenes. For arylallenes the E-vinyl product forms as the major species, while the 1,1-disubstituted alkene is formed in a larger ratio than the Z-vinyl product (e.g., 6:3:1 as E/1,1/Z). The use of H2PPh results in good yields of the 1,1-disubstituted alkene, where the resultant secondary phosphine product does not undergo further reaction. We postulate a catalytic cycle based on spectroscopic data. Employing an [Fe(salen)]2-µ-oxo pre-catalyst leads to phosphine dehydrocoupling rather than hydrophosphination.

Supporting Information



Publication History

Received: 14 June 2022

Accepted after revision: 14 July 2022

Accepted Manuscript online:
18 July 2022

Article published online:
22 August 2022

© 2022. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial-License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/)

Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany