bOtl 500 600 700 nm Figure 6. [MnClI2TMPS-PVPMe+] [TsO-] (dotted lines) in Vaseline.(from 497 to 490 nm) as expected for the coordination of a nitrogencontaining ligand to a manganese por~hyrin.2~Prepantion of [(n-Bu),NJHSO,. Tetra-n-butylammonium monopersulfate was prepared from the potassium salt using the procedure published by Trost et al. with some modifications.26 A 2.0-g sample of potassium monopersulfate (6.5 "01) in 20 mL of water was stirred with 2.0 g of tetra-n-butylammonium hydrogen sulfate (5.9 mmol) for 20 min. Then the solution was extracted with 40 mL of dichloromethane. This organic phase was dried over magnesium sulfate and filtered out. After evaporation, the remaining paste was washed with 10 mL of hexane and dried under vacuum. After evaporation, 0.5 g of [(~-Bu)~N]HSO!, was UV-visible spectra of MnCllzTMPS (full lines) and (25) Kelly, S. L.; Kadish, K. M. Inorg. Chem. 1982, 21, 3631-3639. (26) Trost, B. M.; Braslau, R. J . Org. Chem. 1988, 53, 532-537.obtained with a purity better than 90% (determined by icdometric titration). Ckutiolr: this peroxide should be considered as potentially explosive, and despite the repeated number of safe syntheses, we never overpassed this preparation scale.Typical Proccdure for Cyclooctew Epoxidrtioos Catalyzed by Sup ported Maqanes Porphyria Complexes. A 5-mL flask was loaded with 3 mL of dichloromethane, 20 pL of cyclooctene (154 pmol), 20 pL of 1,2-dichlorobenzene (178 pmol) as internal standard for GC analyses, and 2 pmol of sulfonated manganese porphyrin loaded on 100 mg of PVP (or 2 pmol of sulfonated manganese porphyrin for -250 mg of loaded and protonated or methylated PVP rain). At time zero, 165 mg of PhIO (750 pmol) was added to the stirred reaction mixture. At different reaction times the stirring was stopped to allow the uptake of an aliquot of 1 pL, which was directly analyzed by GC. Concentrations of cyclooctene and cyclooctene oxide were determined after their corresponding response factors. Results described in Figure 5 were obtained starting with 500 pL of cyclooctene (3850 pmol). Typical Procedure for A d a~n t r a e Hydroxylations Catalyzed bySupported l b n p w e Porphyria Cmpkxea. A IO-mL flask was loaded with 525 mg of adamantane (3.86 mfiol), 120 mg of 1,4dibromobenzene (internal standard), 1 pmol of the supported catalyst, and 7 mL of dichloromethane (1 pmol of the supported catalyst equals a loading of 1 pmol of MnCll2TMPS for 100 mg of PVP in the case of [MnCIl2TMPS-PVP], or for -250 mg of [MnCll2TMPS-PVPH+]-[TsO-] or [MnC1lzTMPS-PVPMe+] [TsO-1). At time zero, 165 mg of PhIO (750 pmmol) was added to the stirred reaction mixture at room temperature under air (results were not modified when performed in an argon atmosphere). Aliquots of 1 pL were directly analyzed by GC. Concentrations of 1-admantanol, 2-adamantanol, and adamantanone were determined after their corresponding response factors.Ackmwledgmeat. This work was supported by a "Stimulation" grant from the EEC, including a postdoctoral fellowship for S.C.(on leave from Prs. G....

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The reaction of [Cp*CoClIz, Cp* = q5-C5Me5, with BHyTHF leads to the formation of nzdol-(q5-C5Me5)Co-2-( 4-C5Me5H)CoB3Hg, 1 (60%, monoclinic P21/n, a = 8.076(1), b = 20.359-(2), c = 13.880(2) 1, p = 91.23(1)", V = 2281.7(6) Hi3, d(ca1cd) = 1.251g/cm3, 2 = 4), and 5-C5Me5)CoB4Hl~, 2 (2-lo%, monoclinic P21/c, a = 13.954 (3), b = 14.185(4), c = arachno-(9, 29.383(7) , /? = 100.61(2)", V = 5717(2) A3, d(calcd) = 1.150 g/cm3, 2 = 16) via the metastable paramagnetic intermediate [{(q5-C5Me5)Co}(BH3Cl)l~, 9, with the coproduct BHzC1. Heating 1 leads to nido-2,4-{(q5-C5Me5)Co}2B3H7, 3 (80%, tetragonal P42/n, a = b = 23.440(4), c = 8.317(2) A, V = 4570(1) A3, d(ca1cd) = 1.244 g ~m -~, 2 = 8). The reaction of [Cp*CoClIz with LiBH4 leads to the formation of cZoso-2,3,4-{ (q5-C5Me5)Co}3B2H4, 4 (20%, rhombohedral, R3, a = 17.994 (1) A, c = 15.986 (1) A, V = 4477.3 A3, d(ca1cd) = 1.347 g ~m -~, 2 = 6) and lesser amounts of doso-1 2,3-{(q5-C5Me5)Co 3B3H5, 6 (triclinic, Pi, a = 8.461 (2) A, b = 10.718 (2) { (q5-C5Me5)Co}4B2H4, 6, via the sequential formation of the metastable intermediates [{(q5-C5Me5)Co}(BH4>In, 7 (paramagnetic), and { (q5-Cae5)Co}2B~H6, 8 (diamagnetic). These results demonstrate that a labile metal precursor permits control of the number of metal atoms in the metallaborane and the characterization of unusual and metastable cobaltaboranes. A kinetic study of the conversion of 1 to 3, which involves the intramolecular dehydrogenation of a q4-C5Me5H ligand and skeletal rearrangement, is reported and the mechanistic implications for the origin of 1 are discussed.A, c = 17.591 (4) A, V = 1511.0 (8) A 3, d(ca1cd) = 1.363 g ~m -~, 2 = 2), and closo-1,2,3,6-

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