The cobalt cubium Co4O4(OAc)4(py)4(ClO4) (1A(+)) containing the mixed valence [Co4O4](5+) core is shown by multiple spectroscopic methods to react with hydroxide (OH(-)) but not with water molecules to produce O2. The yield of reaction products is stoichiometric (>99.5%): 41A(+) + 4OH(-) → O2 + 2H2O + 41A. By contrast, the structurally homologous cubium Co4O4(trans-OAc)2(bpy)4(ClO4)3, 1B(ClO4)3, produces no O2. EPR/NMR spectroscopies show clean conversion to cubane 1A during O2 evolution with no Co(2+) or Co3O4 side products. Mass spectrometry of the reaction between isotopically labeled μ-(16)O(bridging-oxo) 1A(+) and (18)O-bicarbonate/water shows (1) no exchange of (18)O into the bridging oxos of 1A(+), and (2) (36)O2 is the major product, thus requiring two OH(-) in the reactive intermediate. DFT calculations of solvated intermediates suggest that addition of two OH(-) to 1A(+) via OH(-) insertion into Co-OAc bonds is energetically favored, followed by outer-sphere oxidation to intermediate [1A(OH)2](0). The absence of O2 production by cubium 1B(3+) indicates the reactive intermediate derived from 1A(+) requires gem-1,1-dihydoxo stereochemistry to perform O-O bond formation. Outer-sphere oxidation of this intermediate by 2 equiv of 1A(+) accounts for the final stoichiometry. Collectively, these results and recent literature (Faraday Discuss., doi:10.1039/C5FD00076A and J. Am. Chem. Soc. 2015, 137, 12865-12872) validate the [Co4O4](4+/5+) cubane core as an intrinsic catalyst for oxidation of hydroxide by an inner-sphere mechanism.

Ford, Hunt, and Waters. 3529 709. Properties and Reactions of Free Alkyl Radicals in Xolution. Part VI? Reuctions with N-Halogenoanilides.By M. C. FORD, L. J. HUNT, and WILLIAM A. WATERS.2-Methoxycarbonyl-2-propyl radicals abstract the N-halogen atom from an N-halogeno-anilide, giving the corresponding methyl a-halogenoisobutyrate together with products derived from the newly formed acylamino-radical, *NAr*COR. From N-chloroacetanilide there is obtained methyl a-9acetamidophenylisobutyrate. N-Chlorobenzanilide gives 4-benzamido-Nbenzoyldiphenylamine, and a similar product results from N : 2' : 4'trichlorobenzanilide. N : 2' : 4' : 6'-Tetrachlorobenzanilide yields both benzoyl chloride and 3 : 5-dichloro-1 : 4-benzoquinone 1-(2 : 4 : 6-trichloroanil) . These results indicate that acylamino-radicals are mesomeric, and couple to give C-C or N-C, and not N-N, bonds.