Metal‐Free Catalytic Hydrogenation

Phosphonium borates of the form R2PH(C6F4)BH(C6F5)2 are shown to be metal-free hydrogenation catalysts (see scheme) that effect reduction of sterically hindered imines and aziridines, as well as B(C6F5)3-protected unhindered imines and nitriles, at relatively low H2 pressures and temperatures. Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2002/2007/z702908_s.pdf or from the author. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.