Albert Einstein
Porphyrinoids, also known as the pigments of life, are a class of naturally occurring organic dyes. They play key roles in crucial processes that support life - oxygen transport (hem), electron transport (cytochrome c), photosynthesis (chlorophyll a), and synthesis of DNA (vitamin B12). Vitamin B12 - a co-factor in many catalytic processes. Following nature, we have been exploiting the potential of this compound in catalysis.
Vitamin B12 - catalysis has been successfully translated into the laboratory and used in a small collection of reactions.[1-2] The advantage of using vitamin B12 as a catalyst lays in the complete stability of the central cobalt ion and by the definition it is nontoxic. It has also been well documented that the reaction mechanism usually follows a radical pathway, bringing a new dimension to this already interesting field.[2]
Along this line, we have developed new vitamin B12-catalyzed reactions involving reduction of Co(III) to Co(I) or Co(II) and subsequent reactions with electrophiles or radicals. Vitamin B12 derivative unusually catalyzes a new olefinic sp2 C-H alkylation reaction with diazo reagents as a carbene source,[3], acylation of activated olefins, alkylation of strained molecules.[4-6] These key findings emphasize the unique feature of vitamin B12 as a catalyst to achieve something unachievable with other methodologies or to find a greener approach.
References
- [1] Banerjee, R. Chemistry and Biochemistry of B12, John Wiley & Sons, Inc, 1999
- [2] Giedyk, M., Goliszewska, K., Gryko, D. Soc. Rev. 2015, 44, 3391-3404.
- [3] Giedyk, M.; Fedosov, S.; Gryko, D. Commun. 2014, 50, 4674-4676.
- [4] Ociepa, A. J. Wierzba, J. Turkowska, D. Gryko, J. Am. Chem. Soc. 2020, 142, 5355-5361.
- [5] Potrząsaj, A.; Musiejuk, M.; Chaładaj, W.; Giedyk, M; Gryko, D ChemRxiv, 2021, 143, 9368–9376. https://doi.org/10.26434/chemrxiv.13559852.v1
- [6] Turkowska, J.; Durka, J.; Ociepa, M.; Gryko, D. Chem. Commun., 2021, DOI https://doi.org/10.1039/D1CC05330B
