Show how the following ketones might be synthesized from the i...

Question

Show how the following ketones might be synthesized from the indicated acids, using any necessary reagents.

(b) methyl cyclohexyl ketone from cyclohexanecarboxylic acid

Accepted Answer

Hey everyone and welcome back in today's video, we are going to propose a method for producing the following key zone from the given car book silic acid Using any additional regions. The reaction states that the starting material, a cyclone fencing carve oxalic acid and the final product that we are producing as method cycle pencil key zone. We can essentially start by drawing out this reaction. It's a cycle pen saying carb oxalic acid. So we're going to draw a cycle plantain ring. So that would be our five member ID ring. And because we have carb oxalic acid, we can essentially bond the carb oxalic acid group to our ring. Right? So that'll be our C O H, which represents the acid. And now according to the problem, we are producing metal cycle pencil ketone. So that will be our psycho pencil substitution. Once again our five member ring. Then, because we have a key zone, we're going to add a carbonell group and it says metal cycle pencils, we're going to add our metal group because we have already assigned our cycle pencil substitution. So we understand that the conversion that we are performing is the conversion from an asset to a key zone. And one of the ways to perform that conversion is to make sure that we are using and or again a lithium reagent. Now to understand what kind of organic lithium region we need, we essentially want to think about the substitution. We have used notice that we have bonded a metal substitution to our carbonell that has replaced the wage group at this position. Right? So that means we are going to use Methyl lithium CH three ally. Right, So that would be method lithium Now, essentially, let's say, let's see how this reaction really works. So what you may recall is that this region is strongly basic. So we will simply redraw our starting material once again to see how step by step we achieve that conversion. Now we are going to expand this acidic hydrogen because we're dealing with a basic region that will be our meth a lithium and we understand that the electrons would end that carbon lithium bond are strongly polarized towards carbon. So the region is strongly basic and this is our acidic protons. So in the first step we are going to d protein eight, that acidic proton because the region is strongly basic and it refers to attack that most acidic hydrogen in the structure. And then when we have the proton capture, we're transferring the electrons onto oxygen. And this is how we produce our carb oxalate and ion we may some play for the resulting structure. For this step, That would be our five member ring car box late and we may also add lithium as an iron spectator. All right, now, this was just the addition of the first equivalent notice that we haven't achieved the presence of that metal group. So the second equivalent of meth a lithium essentially will attack the electra filic position of our car box allayed. So you may simply say that meth a lithium attacks the carbonell group or basically the carbon within the carbon group. And then we're breaking the pi bon. We're essentially creating another elk oxide and iron over here. Right now, that would be our next in the immediate let's draw it out so that we are five member ring. Now we notice that we have two single bonded oxygen's and now this one is auction with a negative charge as well because we have broken the pi bond and we have transferred the bonding electrons onto oxygen. So we have another lithium as an iron spectator. In addition to that, you may notice that we have added our metal groups. So we are going to add it over here and this is a stable diane ion essentially it has two negatively charged oxygen atoms. And we are nearly done. We just need to make sure that we perform the acidic work up. Now in the first step of the stick work up, we're going to perform the protein nation step. So the T. N ions are basically the two negatively charged oxygen atoms will get protein ated and we will produce two alcohol groups. So let's see how that looks like. So we can draw the metal group. Then we have O. H. Right? It has been protein ated and then we have another wage instead of these two negatively charged oxygen atoms. So this is the first step then the asset is used in the protein nation stop of one of the alcohol groups. So the lone pair on oxygen. Guess protein needed. Once again that would be our hydro ni. Um we are essentially capturing the acidic proton which is followed by the loss of the water molecule. Let's draw the result on intermediate here. So once again that will be our five member ring. Now this alcohol group now becomes H 20. With a formal positive charge. And then we have O. H. Now because we have a water molecule present with a positive charge. That's a perfect leaving group for us. Right? And recall that it can simply be removed from the structure if we use the lone pair on oxygen from this alcohol group. Because you may simply notice how we can form that pi bon and then get rid of the water molecule. Right? So we are forming our next intermediate which now looks very close to the final structure. Right? So we may some play draw our five member ring. We may notice that we have the dessert metal group. And now what remains that will be our oh age with a former positive charge and oxygen. And now in the world last stop the water molecule that left previously will essentially act as a proton except er so we will d protein ate the carbonell group and we will get our final product. So the final product is now ready to be drawn. We may notice that now we have a simple key zone that we needed to get. Okay, so we understood the steps required for this reaction, we understood that we need to separate reactions reaction number one addition of meth a lithium followed by acidic hydrology. Sis keep in mind that we needed to equivalents of meth a lithium. So we may simply go back to our synthesis scheme and we can label two steps needed for this reaction. Step number one, that would be addition of two equivalents of method lithium and step number two would be the acidic hydrogen as a stop in which we form our desired ketone. So our final answer would include this reaction scheme where we start with our assets, get our key tone using these two steps. Now, the correct answer choice to the small pole choice question is a However, if you have any questions, don't hesitate to leave a comment down below and thank you for watching

Show how the following ketones might be synthesized from the indicated acids, using any necessary reagents.
(b) methyl cyclohexyl ketone from cyclohexanecarboxylic acid

Key Concepts

Ketone Synthesis

Carboxylic Acids

Nucleophilic Acyl Substitution

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