This disfavors return to the acyclic glucose, shifting the equilibrium to the right, and thus accelerating the reaction overall. The acid would be Enz-H and the base would be an enzyme lone pair. Protonation of the carbonyl oxygen leads to an oxonium ion that can stabilize the positive charge by resonance. No such resonance is possible when the hydroxyl oxygen is protonated. An organometallic compound is a compound that has a carbon-metal bond.
Carbon is more electronegative than any metal.
This d - on the carbon end represents a slight electron surplus, thus making the carbon end nucleophilic. Grignard reagents are strong bases, and so would be rapidly protonated by water present in any living cell. In addition, formation of a Grignard reagent usually required Mg metal which is not found in a living cell. Select the faster reaction of each pair and briefly explain your choice. Write a complete and detailed curved arrow mechanism for the formation of the major product.