[curiouscat]

Are there any routes to making (P) starting from (R) ?

The one route I found in patents to make (P) was starting at phenol   

      

Noting the obvious similarities of P to R (and having a commercial interest in starting from P) I was wondering if there were any routes worth exploring starting from R?

[Vidya]

First convert vinyl group to electron donating group.Then due to acetylation  which will go to para position.

[darkdevil]

I would start with the dirt cheap 4-hydroxybenzaldehyde --(acetylation)-->  4-Acetoxybenzaldehyde --(Wittig)--> Your Product

It is almost immposible or tedious to start with styrene. Styrene is considerably unstable. Any changes in chemical environment (eg. acid, base, light or oxygen) may polymerize the vinyl group. I am working on polymer and I usually make the vinyl group in the last step of my syntheses. Hope it helps

[curiouscat]

I would start with the dirt cheap 4-hydroxybenzaldehyde --(acetylation)-->  4-Acetoxybenzaldehyde --(Wittig)--> Your Product

It is almost immposible or tedious to start with styrene. Styrene is considerably unstable. Any changes in chemical environment (eg. acid, base, light or oxygen) may polymerize the vinyl group. I am working on polymer and I usually make the vinyl group in the last step of my syntheses. Hope it helps

Thanks! I will think about that.

Dirt cheap is relative. 4-hydroxybenzaldehyde looks like 5 to 6 times as expensive as styrene.

[discodermolide]

How about  a Diels-Alder reaction between

and

[curiouscat]

Thanks @disco. Are either / both of those common feedstocks?

Looked exotic starting points to me. Especially for a commercial route.

[discodermolide]

Sorry but I've no idea about their availability.

[orgopete]

Dirt cheap is relative. 4-hydroxybenzaldehyde looks like 5 to 6 times as expensive as styrene.

I understand the nature of the challenge. Given the nature of seeking a more economical route, I would think you could limit the possible routes and starting materials with your target price.

If you want to use styrene, then you need to have a functionalization reaction. I would think you could search for any electrophilic reactions that succeed. Are there any? Given that challenge, let me suggest an obvious strategy, reverse the process. Wikipedia reports, "Styrene is produced in industrial quantities from ethylbenzene, which is in turn prepared on a large scale by alkylation of benzene with ethylene." I would think phenyl acetate would be a more reactive reactant than benzene. Can't you use the remainder of the styrene reactions from 4-ethyl-1-acetoxybenzene? Or simply start with ethylbenzene? I'm presuming it is cheaper than styrene.

[curiouscat]

I understand the nature of the challenge. Given the nature of seeking a more economical route, I would think you could limit the possible routes and starting materials with your target price.

If you want to use styrene, then you need to have a functionalization reaction. I would think you could search for any electrophilic reactions that succeed. Are there any? Given that challenge, let me suggest an obvious strategy, reverse the process. Wikipedia reports, "Styrene is produced in industrial quantities from ethylbenzene, which is in turn prepared on a large scale by alkylation of benzene with ethylene." I would think phenyl acetate would be a more reactive reactant than benzene. Can't you use the remainder of the styrene reactions from 4-ethyl-1-acetoxybenzene?

Thanks! I will think about this option.

Or simply start with ethylbenzene? I'm presuming it is cheaper than styrene.

Surprisingly EB is currently ~30% more expensive than Styrene.  But same ballpark. 30% isn't huge. Yields etc. might easily make up for that.

[orgopete]

Or simply start with ethylbenzene? I'm presuming it is cheaper than styrene.

Surprisingly EB is currently ~30% more expensive than Styrene.  But same ballpark. 30% isn't huge. Yields etc. might easily make up for that.

Process chemists can probably answer this better than I, but sometimes a price can be higher due to a lack of demand, a reverse of why styrene is so cheap. I wouldn't expect a lot of people buying ethylbenzene just to make their own styrene even if the price were less. I think this is where you can begin to learn chemistry. If you begin with bulk prices and apply processing costs and yields, you can understand the cost of goods. If you are thinking of production, you can also step back to benzene and calculate ethylbenzene from there.

I would also suggest checking the patent literature more carefully. I would be shocked that I could suggest a patentable route in a chemistry forum wondering about alternate routes to a potential commercial product. I don't know this, but I'm not going to hold my breath waiting for anyone to contact me for my signature on their patent application. It is a lot more likely someone thought of this way before me.

[curiouscat]

Process chemists can probably answer this better than I, but sometimes a price can be higher due to a lack of demand, a reverse of why styrene is so cheap.

Agreed. OTOH, it is what it is. My scales are a drop in the ocean of both Styrene & EB consumpytion. I'm a price-taker not a price-maker. 

 

I think this is where you can begin to learn chemistry. If you begin with bulk prices and apply processing costs and yields, you can understand the cost of goods. If you are thinking of production, you can also step back to benzene and calculate ethylbenzene from there.

I agree with you on the pedagogical merits. Unfortunately most Chemistry & Chem. Engineering education is awful at conveying any price related insights. I always thought this was a big hole in the curriculum. You'd have to trawls hundreds of pages of books before finding any price numbers anywhere.

I would also suggest checking the patent literature more carefully. I would be shocked that I could suggest a patentable route in a chemistry forum wondering about alternate routes to a potential commercial product.

The one route I found in patents starts from phenol. See my first post.