Nigel Aylward



A Prebiotic Surface Catalyzed Photochemically Activated Synthesis of 5,6-Dimethylbenzimidazole of Vitamin B12

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Alkynes such as but-2-ynimine and but-2-yne nitrile form weak charge-transfer complexes with catalysts such as Mg.porphin centered on the Mg++ ion and a pyrrole nitrogen. With two bonded adducts electromagnetic excitation produces a high energy bicyclic complex. Further reaction with molecular hydrogen produces a bound di-nitrilo complex and then a di-imino complex that separates from the catalyst. Reaction with formaldehyde produces the rare base 5,6-dimethylbenzimidazole found in Vitamin B12. The reactions have been shown to be feasible from the overall enthalpy changes in the ZKE approximation at the HF and MP2 /6-31G* level.


5,6-dimethylbenzimidazole ,Mg.porphin , but-2-ynimine, but-2-yne nitrile, cyanogen


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Cite this paper

Nigel Aylward. (2018) A Prebiotic Surface Catalyzed Photochemically Activated Synthesis of 5,6-Dimethylbenzimidazole of Vitamin B12. International Journal of Biochemistry Research, 3, 40-46


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