Mara O. Nestle

Organocobalt cluster complexes : XII. The arylation and alkylation of methylidynetricobalt nonacarbonyl with organomercury compounds☆

Abstract The reaction of diarylmercurials and arylmercuric halides with methylidynetricobalt nonacarbonyl in benzene or THF at reflux results in formation of benzylidynetricobalt nonacarbonyl complexes, ArCCo3(CO)9, in good yield, especially when the reactions are carried out under an atmosphere of carbon monoxide. The alkylation of HCCo3(CO)9 with dialkylmercurials or alkylmercuric halides proceeds much more slowly and in much lower yields. Similar reactions of (α-haloalkyl)mercurials, (RCHX)2Hg, with HCCo3(CO)9, gives reduced products, RCH2CCo3(CO)9, rather than the expected RCHXCCo3(CO)9. Similar arylation of the apical carbon atom of the CCo3 cluster occurred in the reactions of XCCo3(CO)9 (X = Cl, Br, I) with diphenylmercury, and in reactions of tetraphenyltin and tetraphenyllead with HCCo3(CO)9.

Organocobalt cluster complexes XXIX. Novel silicon compounds containing the nonacarbonyl tricobaltcarbon substituent

Abstract The reaction of bromomethylidynetricobalt nonacarbonyl or, more effectively, of methylidynetricobalt nonacarbonyl with diverse silicon hydrides (R 3 SiH, Ph 3 SiH, Me 2 (EtO)SiH, R n Cl 3 -n SiH ( n = 02), etc. results in formation of silylmethylidynetricobalt nonacarbonyl complexes. Silicon-functional interconversions such as SiCl → SiOH, SiCl → SiOMe, SiOH → SiF, and SiOH → SiOSiMe 3 , have provided still other substituted silylmethylidynetricobalt nonacarbonyl complexes, generally in high yield. The compounds Me(HO) 2 SiCCO 3 (CO) 9 and (HO) 3 SiCCo 3 (CO) 9 have been incorporated into methylsilicone polymers by H 2 SO 4 -induced reactions with cyclo-(Me 2 SiO) 3 .

Organocobalt Cluster Complexes. XXIII. Clemmenszn and Borane Reductions of Acyl-and Vinylic Methylidynetri-Cobalt Nonacarbonyl Complexes

Abstract The Clemmensen reduction is an effective means of converting acyl- and vinylic methylidynetricobalt nona-carbonyl complexes to the corresponding saturated alkylidynetricobalt nonacarbonyl when it is carried out in nonaqueous medium. Diborane in tetrahydrofuran reacts with acyl-substituted cobalt clusters to give a mixture of the corresponding alcohol and alkyl complexes in which the latter predominates.