[Albacoide]

Hello,

I'm an engineer who's struggling with a homework that's not my field.

I have to assess the greenness of a process to produce a particular drug (capecitabine).

The professor gave us a patent, in which there are examples of the synthesis, from which we have to calculate the green metrics.

The thing is, the amounts of chemicals used in different parts (for extractions, drying, cristalizations) are not specified.

Since this is kind of an emergency, I was thinking of making up coherent values for these processes.

Is there a place where I can look for these values?

Thank you in advance.

[Arkcon]

Basically, a patent is always deliberately written to be as obtuse and nonspecific as possible, so it can't be copied easily.  So its no surprise the exact volumes aren't included.  Since you've been assigned to evaluate the "greenness"of a process, you can probably describe the volumes stoiciometrically.  Or for non-reactions (washing steps as an example) come up with a general idea, define it and just go with it.

On some levels, this sounds like quite a tough project.  How, quantitatively, "green" one process is over another seems like a murky question to me.  I suppose its greener to use a process that washes with isopropanol vs one that recrystallizes from THF, but how much?  Furthermore, if you mix a compounded pharmaceutical formulation with actives, excipients, binding agent and water, that's "greener" that using isopropanol with the water as a solvent.  Unless of course, the tableting fails when you do that.  Which actually happened, where I once worked.

[billnotgatez]

@Albacoide
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[orgopete]

It is always difficult to answer a question for a class I didn't attend. None the less, I suggest you assume the solvents are completely recyclable. Therefore, except adding to processing costs, they don't contribute to the net carbon economy. I don't know how greeness is determined for your class, but I suspect it has to do with carbon economy. If so, you should be able to determine this facet assuming yields have been given for the examples. This will probably still require you to calculate the MW, moles, yields, etc.

Obviously, I don't know what is being asked, but I am simply assuming you have been given enough information to answer the question.

[Babcock_Hall]

The forum policy here is to help you after you show us what you have already done.  With respect to this problem, you might start by finding and listing some principles of green chemistry, for example.