Syntheses, Structures and Reactivities of Rhodium 4,5-Diazafluorene Derivatives

✍ Scribed by Huiling Jiang; Elzbieta Stepowska; Datong Song

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 296 KB
• Volume: 2009
• Category: Article
• ISSN: 1434-1948
• DOI: 10.1002/ejic.200801195

✦ Synopsis

Abstract

Four rhodium 4,5‐diazafluorene derivatives, [RhL(PPh~3~)~2~] (1), [Rh(H)~2~(LH)(PPh~3~)~2~]Cl (2), [Rh(H)~2~L(PPh~3~)~2~] (3) and [Rh(H)~2~(LH)(PPh~3~)~2~]OTf (4), have been synthesized and fully characterized by NMR spectroscopy, elemental analysis and single‐crystal X‐ray diffraction. Compound 1 can be converted into 3 when treated with hydrogen gas. Compound 2 can be converted into 3 when treated with NaH, and the reverse reaction can be achieved by treating 3 with aqueous HCl. The air‐ and moisture‐stable compound 2 is an active catalyst for the hydrogenation of a variety of olefins, including non‐terminal ones; the chloride counterion in 2 appears to play a role in the catalytic system. Thus, compound 4, the triflate analogue of 2, is inactive towards olefin hydrogenation.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)