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Cobryketone derived from vitamin B12 via palladium-catalyzed cleavage of the sp3-sp3 carbon-carbon bond.

Cobryketone derived from vitamin B12 via palladium-catalyzed cleavage of the sp3-sp3 carbon-carbon bond.

The Journal of organic chemistry (2013-04-03)

Sylwester Kurcoń, Keith ó Proinsias, Dorota Gryko

ABSTRACT

Heptamethyl cobyrinate was transformed into hexamethyl 8-nor-cobyrinate. The crucial step involved the synthesis of new, vitamin B12 derived cobryketone via palladium-catalyzed cleavage of the sp(3)-sp(3) carbon-carbon bond with the liberation of the ketone. The replacement of sp(3) carbon atom with sp(2) (C═O) at the 8-position produces a bathochromic shift of all absorption bands and makes α and β bands equal as a consequence of the expansion of the existing conjugated system of double bonds.

MATERIALS

Product Number

Brand

Product Description

Supelco

Cyanocobalamin, pharmaceutical secondary standard, certified reference material

Supelco

Cyanocobalamin (B12), analytical standard

Sigma-Aldrich

Palladium, nanopowder, <25 nm particle size (TEM), ≥99.5%

Sigma-Aldrich

Palladium, wire, diam. 1.0 mm, 99.9% trace metals basis

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Palladium, powder, <1 μm, ≥99.9% trace metals basis

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Palladium, foil, thickness 0.5 mm, 99.9% trace metals basis

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Palladium, powder or granules, 99.99% trace metals basis

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Palladium, foil, thickness 1.0 mm, 99.9% trace metals basis

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Palladium, powder, 99.995% trace metals basis

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Palladium, wire, diam. 0.5 mm, 99.9% trace metals basis

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Cyanocobalamin (Vitamin B12) solution, 1.0 mg/mL in methanol, ampule of 1 mL, certified reference material, Cerilliant^®

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Vitamin B₁₂, BioReagent, suitable for cell culture, suitable for insect cell culture, suitable for plant cell culture, ≥98%

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