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Published on: March 20, 2017
A Cerium Yldiide Complex with a Ce←←C Double Dative Bond
1School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu 241000, China.
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Methandiides, bisylides, and yldiides are geminal dianions having two lone pairs of electrons at the central carbon atom and are applicable to construct f-block carbon multiple-bond complexes. However, cerium yldiide complexes possessing a cerium-carbon double bond are not known to date. Herein we report cerium yldiide complex 4 which bears a short Ce-C bond of 2.461(5) Å, exhibiting significant cerium-carbon multiple-bond character. The nature of the Ce-Cmethine bond in 4 was probed by DFT, unveiling a rare CeC double dative bond. Therefore, 4 is the first cerium yldiide double-bond complex. Complex 4 underwent nucleophilic addition toward ClBPh2 to give 5 incorporating a borate-functionalized ylide. These findings may provide straightforward access to lanthanide yldiide multiple-bond complexes from lanthanide ortho-metalated ylides.
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