title: Cobryketone derived from vitamin B12 via palladium-catalyzed cleavage of the sp3-sp3 carbon-carbon bond.
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.
authors.affiliation: Institute of Organic Chemistry PAS, Kasprzaka 44/52, 01-224 Warsaw, Poland.
authors.forename: Sylwester
authors.initials: S
authors.lastname: Kurcoń
authors.forename: Keith ó
authors.initials: Kó
authors.lastname: Proinsias
authors.forename: Dorota
authors.initials: D
authors.lastname: Gryko
mesh_terms: D002384:Catalysis; D004583:Electrons; D007659:Ketones / Q000737:chemistry*; D015394:Molecular Structure; D010165:Palladium / Q000737:chemistry*; D014805:Vitamin B 12 / Q000737:chemistry*
chemical_list: D007659:Ketones; D010165:Palladium; D014805:Vitamin B 12