17) A complex of stoichiometry MnCp2(C4H80)2 (C4HsO is tetrahydrofuran) (18) M. F. Rettig and R. S. Drago, J. Amer. Chem. SOC., 91, 1361 (1969). (19) M. F. Rettig and R. S. Drago, J. Amer. Chem. SOC., 91, 3432 (1969). (20) For the calculation of AH, we used the usual equation (see eq 7 of ref (1964). was isolated (ref 2). 18). Since MnCp2 is "high spin" in solution (ref 2), we used g = 2.0, T = 310°K, S = 12.(21) (a) The ' A,, ground state for gaseous MnCp2 was proposed (ref 30) on the basis of photoelectron spectroscopy results. Orchard and coworkers (ref 4) have however disputed the necessity of invoking the ZA,g state to account for the PE spectrum.(33) Anderson and Rai (ref 22) estimate that the Kramers doublet derived from *A,, in FeCp2+ lies only ca. 260 cm-' above the lower Kramers doublet from ' E2, . (34) J. A.Abstract: Palladium atoms oxidatively insert aryl, alkyl, and acyl carbon-halogen bonds at low temperature to yield a new series of reactive intermediates ArPdX, RPdX, and RCOPdX. Efficiency of the insertion is in the order C-I > C-Br > C-CI. These species are formed in the absence of normal stabilizing ligands and their stabilities vary greatly depending on the organic group attached. For example ChFjPdBr is stable at room temperature in the air whereas CH3Pdl decomposes at exdihalide complexes were colored (yellow for chloride and bromides, orange for iodides) while the organopalladium complexes were white.

A new technique for the direct synthesis of nonsolvated fluoroorganic zinc compounds has been employed in our laboratories. Zinc atoms have been cocondensed with fluoroalkyl iodides on a liquid nitrogen cooled surface in the manner previously described by Skell and coworkers1 for the study of carbon atoms added to the residue (without pyrolysis) trace quantities of fluoroform and TFE were formed. If the CF3I vapor was saturated with water vapor before deposition, a good yield of fluoroform resulted, but hexafluoroethane and TFE were still formed.These results indicate that the fluoroorganic zinc compound formed is unstable at well below room temperature and can be hydrolyzed by water while quite cold. Similar and more striking results were found upon the reaction of zinc atoms with heptafluoroisopropyl iodide saturated with water vapor. The

Et-+ (CH3)3CNO ->- EtN-z-Bu The use of IrCl62as an efficient scavenger for alkyl radicals is implied in Scheme I (eq 5) by the isolation of alkyl chlorides in high yields (even in the presence of a hundredfold excess of bromide ion8). In support, separate experiments do show that ethyl radicals generated unambiguously from the thermolysis of propionyl peroxide are quantitatively converted by IrCl62to ethyl chloride.9The reaction mixture consisting of reduced iridium-(III) species was reoxidized with either chlorine or lead dioxide, and the iridium(IV) was separated by silica gel chromatography. We deduce from the subsequent analysis of IrIVCl62~that one-half of the iridium(III) formed in the reaction consisted of IrniCl63-in accord with eq 3 of Scheme I. The remainder of the iridium-(III) appears as an insoluble polynuclear species and the fate of IrnICI52-formed in eq 5 has not yet been clarified.(8) Added as the quaternary ammonium salt. Compare S. N.

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