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Sulfate Separation by Selective Crystallization with a Bis-iminoguanidinium Ligand
Published on: September 8, 2016
A stable bis(methylene)-λ4-selane with a >C[double bond, length as m-dash]Se[double bond, length as m-dash]C< bond
K Sugamata1, Y Urao1, M Minoura1
1College of Science, Department of Chemistry, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima-ku, Tokyo 171-8501, Japan. sugamata@rikkyo.ac.jp.
Abstract:
Bis(methylene)-λ4-selane 1, which represents a new class of heteroallenes, was synthesized and isolated as a stable purple crystalline solid. X-ray crystallographic analysis revealed a bent allene-type structure with pseudo C2v symmetry and a bent C[double bond, length as m-dash]Se[double bond, length as m-dash]C moiety that contains a 3-center-4-electron π-bond. The NMR spectrum of 1 shows compelling evidence for a slow rotation of the Se[double bond, length as m-dash]C moieties at room temperature. The 77Se NMR spectrum of 1 contains one signal in the region characteristic for Se(iv) compounds.
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