Osmium porphyrins synthesis

Synthesis and structure of ruthenium and osmium porphyrin carbene complexes and their role in the metal-mediated cyclopropanation of alkenes 02CCR(231)151. 

The first ruthenium porphyrin-catalyzed intramolecular carbenoid C - H insertion to afford selectively cis-2,3-disubstituted-2,3-dihydroergocornine using tosylhydrazone salts as the carbene source was reported by Zheng et al. [192]. This general strategy was applied in natural product synthesis to provide a route to the total synthesis of racemic epi-conocarpan. Enantio-selective synthesis of 2,3-dihydrobenzofurans was also achieved by a similar route using chiral ruthenium porphyrins as catalysts for this interesting carbon-carbon bond formation [193]. Recently, it was found that dinuclear fx-oxo osmium porphyrins are able to catalyze intermolecular carbene insertion into C - H bonds in cyclohexene [153]. 

Kariya. N. Imamura. T. Sasaki, Y. Synthesis, characterization, and spectral properties of new perpendicularly linked osmium(III) porphyrin. Inorg. Chem. 1997,36. 833. 

Kariya, N., T. Imamura, and Y. Sasaki (1998). Synthesis and properties of osmium(II) porphyrin oligomers linked by 3-pyridylporphyrins. Inorg. Chem. 37, 1658-1660. 

The synthesis of porphyrinoids containing nonpyrrolic heterocycles is of interest for studying the intrinsic properties of porphoryins. These porphyrin-like molecules possess varying absorption and emission properties and abilities to interact with metals or other analytes. Akhigbe and Bruckner converted meso-tetraphenylporphyrine 140 to diketone 141 using osmium tetroxide and DDQ oxidation (Scheme 5.33T Oxime formation followed by a... 

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