No abstract

Oxidation favors oxidative addition: This unexpected behavior has been observed in d8d8 ‘open‐book' diiridium complexes with alkene ligands, which become C−H activating after oxidation with ferrocinium salts (see scheme).

The infrared multiple photon dissociation of CH2CDF proceeds by 3- and 4-center eliminations, in agreement with the predictions of recent ab initio calculations. IR spontaneous emission is detected from HF† and from a species tentatively identified as C2H2† produced from the vinylidene⇄acetylene isomerization which follows 3-center elimination. We are unable to detect emission from DF†, indicating that this vibrationally excited species is not a major product. GC/MS analyses indicate that the 3- and 4-center pathways account for approximately 30% and 70%, respectively, of the decomposition. There is no evidence of an ethylidene intermediate, suggesting that the barrier for 1,2 H migration is higher than predicted by ab initio calculations.

levels are unable to reproduce the experimental findings, suggesting that the trans form is slightly more stable. In the gas phase we find no evidence of the presence of a second conformer, and we know that the cis form is both present (from the microwave spectrum)19 and predominant (from the electron diffraction study),7 but we still cannot exclude the possibility that a small proportion of a second conformer is also present in the gas phase.Acknowledgment. The authors gratefully acknowledge financial support of this research by the National Science Foundation by Grant CHE-83-11279 and the NATO Scientific Affairs Division through their collaborative research program under Grant No. 140/82. Registry No. CH3CH2NCO, 109-90-0.