Carbon hex

Might chemists have at last synthesized a hexavalent carbon compound? The X-ray structure and computational analysis of a compound with a central allenic carbon atom flanked by four oxygens would suggest so. Torahiko Yamaguchi of the University of Hiroshima, Japan, and colleagues crowded out an allenic carbon with two hefty sulphur-containing ligands based on reducing thioxanthone and took an X-ray snapshot. The sulphur ligands take up the allenic bonds north and south of the carbon atom with four oxygens then ringing the carbon to complete the octahedral arrangement. It certainly looks like those C to O distances are short enough to be bonds, and may not be simply jammed together. But, while there may be some kind of stabilizing force between the carbon and oxygens and the distances are well within van der Waals radii, the best that one can say at this point is that the carbon is probably hexacoordinate but probably not hexavalent.