Semibridging

Fig. 1. Structure of the active site of H0I as determined by x-ray crystallography (41). Broken lines are used to designate hydrogen bonding of the water molecule to Glu 114 and Glu 243, as well as the semibridging interaction of Glu 144 with the diiron center.

Hexafluorophosphate derivatives, such as [M(Me2SO)n][PF6]3 (M = La, Lu, Y), have been synthesized (365), and infrared data show O-bonding of the sulfoxide with ionic hexafluorophosphate groups. Analytical data are incomplete for this series, as decomposition, postulated to be to lanthanide fluorides, occurs. The (CH2)4SO complexes [M( CH2 4SO)t.5][PF6]3 are reported (145), which are 3 1 electrolytes with uncoordinated anions, implying a possible semibridged structure, as previously mentioned. Complexes of other cyclic sulfoxides, including thioxane oxide (146) and trans-1,4-dithiane-1,4-dioxide (147) derivatives of hexafluorophosphate salts have also been prepared. 

Choukroun, R.. Iraqi, A.. Gervais, D., Daran, f.C. and Jeannin, Y. (1987) A semibridging hydrido zirconium-rhodium complex A possible way to catalytic hydrogen transfer on do-de systems. Organometallics. 6. 1197-1201. 

Reaction of the semibridging methylidyne cluster Os3(/i-H)Oi3-CH)(CO)10 with Pt(C2H4)2(PCy3) affords the tetranuclear 62-CVE carbido species Os3Pt(/i-H)2(/i4-C)(CO)j0(PCy3) (88), together with a pentanuclear Os3Pt2... 

A rotated structure that yields a bridging or semibridging CO ligand and... 

The CNC bonds are greatly bent with angles 120°C. There may also be exchange between terminal and bridge groups, as in Fe2(/ -CNEt)3(CNEt)6, possibly via semibridged species. One example of triply bridging isocyanide is... 

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