Iron-PNP-Pincer-Catalyzed Transfer Dehydrogenation of Secondary Alcohols.

The well-defined iron PNP pincer complex catalyst [Fe(H)(BH4 )(CO)(HN{CH2 CH2 P(iPr)2 }2 ] was used for the catalytic dehydrogenation of secondary alcohols to give the corresponding ketones. Using acetone as inexpensive hydrogen acceptor enables the oxidation with good to excellent yields. DFT computations indicate an outer-sphere mechanism and support the importance of an acceptor to achieve this transformation under milder conditions.