I’m confused, first you said that the electrons from the carbon-carbon double bond will shift up to create a carbon oxygen double bond but then you show a completely different mechanism when giving an example, you show that the oxygens lone pairs create the oxygen carbon double bond. You also stated that the hydrogen on the oxygen would shift over to bond with the carbon on the right and then you showed a completely different mechanism in the example, you showed the carbon double bond attacking the hydrogen from the water molecule. So what is actually happening in the mechanism?
Hi! The mechanism shows the correct movement of atoms and electrons in the tautomerization process. The hydrogen that gets relocated is not moving within the same molecule. The water acts to remove the H from one molecule and then place it onto the carbon of a different molecule. With regards to the double bond, the phrases I used are "swaps" and "changing places", referring to the location of the pi bond within the molecule. I did not intend to imply that the pi bond electrons move directly from one bond to the other.
Yes, hydroboration-oxidation is always anti-Markovnikov. The two-step reaction with the boron reagent is the hydroboration-oxidation reaction. In this video, I show it with Sia2B, but there are several reagents that work equally well. I don't draw out the mechanism for the hydroboration-oxidation reaction, I just show the overall reaction.
so happy I stumbled upon your page! This breakdown helped me understand this mechanism a lot better. Thank you :)
I’m confused, first you said that the electrons from the carbon-carbon double bond will shift up to create a carbon oxygen double bond but then you show a completely different mechanism when giving an example, you show that the oxygens lone pairs create the oxygen carbon double bond. You also stated that the hydrogen on the oxygen would shift over to bond with the carbon on the right and then you showed a completely different mechanism in the example, you showed the carbon double bond attacking the hydrogen from the water molecule. So what is actually happening in the mechanism?
Hi! The mechanism shows the correct movement of atoms and electrons in the tautomerization process. The hydrogen that gets relocated is not moving within the same molecule. The water acts to remove the H from one molecule and then place it onto the carbon of a different molecule. With regards to the double bond, the phrases I used are "swaps" and "changing places", referring to the location of the pi bond within the molecule. I did not intend to imply that the pi bond electrons move directly from one bond to the other.
Which part exactly of this lecture is the hydroboration-oxidation mechanism? Is this mechanism always anti-markovnikov?
Yes, hydroboration-oxidation is always anti-Markovnikov. The two-step reaction with the boron reagent is the hydroboration-oxidation reaction. In this video, I show it with Sia2B, but there are several reagents that work equally well. I don't draw out the mechanism for the hydroboration-oxidation reaction, I just show the overall reaction.
Hello!! can u explain what is the role of Hg here? is there any cyclic mercury Ring is formed?
I am here just before my grade 12 chemistry board exam
Good luck!