POST-EXAM CHAT: OCR Chemistry- Rings, Polymers and Analysis - F324 thread

The point is that there isn't going to be a halogen carrier in the reaction mixture, so it's impossible for that to be formed. The question asked what impurity could be formed in the reaction, it's impossible for that to be formed.

It will reduce carboxylic acids, it says that they do in both the Cambridge book and the Smith & Older book.

NaBH4 will only reduce carboxylic acids under certain conditions: (quoted):
Oxidation of NaBH4 with iodine in tetrahydrofuran gives the BH3-THF complex, which can reduce carboxylic acids. Likewise, the NaBH4-MeOH system, formed by the addition of methanol to sodium borohydride in refluxing THF, reduces esters to the corresponding alcohols, for instance, benzyl benzoate to benzyl alcohol.

It won't do it by itself.

you know what was great?
the massive absence of green chemistry

You're not going to get it wrong by putting NaBH4 though, as it's perfectly acceptable for this specification.

The question specifically said name or list the sequence of amino acids, so sorry but you are wrong.

Well, of course, I would be glad if that were to be the case as I would gain the marks - but you would have also needed to state those extra bits in the answer to gain the marks probably, and that is quite complex, definitely beyond the scope of this course. It isn't mentioned in the textbook.

You know what you're absolutley on the dot. Normally I hate green chemistry but looking at this paper...I miss greeen chemistry like a *****.

You're not going to get it wrong by putting NaBH4 though, as it's perfectly acceptable for this specification.

ahhhh I ran out of time too and that OH on the aldehyde group confused me My school arent even gonna let us retake this unit

i went back through and realised i had just wrote valine! quickly changed that

why do they have any say in that? evil people
my school dont mind as long as you supply the £££
if you reallllyyy want to cant you just retake it at another place?

NaBH4 is lame ffs cant even reduce a ******* carboxylic acid

I just wrote valine, and because I was messing around with the other questions, I didn't have enough time. Was that worth 1 mark?

Well, they recommend you don't do it because the June module is so huge and they say you should retake AS modules....I duno..I guess if I persuaded them into it they would let me! Yeah retaking it somewhere else is also an option...see what I get in March though hey?