Abstract
The chemistry of late-transition-metal carbene complexes has recently received much attention, primarily due to the high catalytic activity of phosphine ruthenium carbene complexes in olefin metathesis.1,2 The most useful Ru carbene in these series is Grubbs' catalyst, (PCy3)2Cl2RuCHPh, bearing a benzylidene unit.1 Being highly active and remarkably tolerant to common functional groups, this compound found broad applications in both organic2b,c and polymer chemistry.2d,e Therefore, synthesis and investigation of late-metal benzylidene complexes (MCHPh) is a topic of great interest.1-4a There are several synthetic approaches toward alkylidene complexes,4 with the ones utilizing the corresponding diazoalkane being the most popular.1,2,5 However, the instability of diazo compounds and the safety issues involved in handling them seriously limit this method. Another recent approach, involving the reaction of precursors to unstable Ru(0) complexes with alkyl dihalides,6 is limited by the difficult synthesis of the unstable Ru(COD)(COT) precursor.7 New approaches toward Ru−alkylidenes starting from Ru−hydride complexes and utilizing alkyne or alkene functions were reported recently.8 Here, we present a new, synthetically simple and safe method toward carbene preparation by using sulfur ylides as carbenoid precursors.9 Such ylides are extensively used in organic chemistry.10 To our knowledge, there are no examples for the synthesis of metal carbene complexes by using these compounds, although metal complexes of sulfur ylides are reported.11,12 Also, the “transylidation” reaction, transfer of a carbenoid unit between heteroatom centers, is well-known among main group elements.13 The new synthetic route is general and can be applied to different metals. Moreover, it can be used for the synthesis of carbene complexes which could not be prepared by known methods.
Original language | English |
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Pages (from-to) | 5372-5373 |
Number of pages | 2 |
Journal | Journal of the American Chemical Society |
Volume | 123 |
Issue number | 22 |
DOIs | |
Publication status | Published - 2001 |
Funding
This work was supported by the Israel Science Foundation, Jerusalem, Israel, and by the Tashtiot program of the Israeli Ministry of Science. D.M. is the holder of the Israel Matz Professorial Chair of Organic Chemistry. We thank Yehoshua Ben-David for technical assistance.
All Science Journal Classification (ASJC) codes
- General Chemistry
- Biochemistry
- Catalysis
- Colloid and Surface Chemistry