OCR F324-June 2013 Chemistry

the reaction will be slow froming an ester

glutamic acid is refluxed with excess ethanol and and concentrated h2so4 catalyst. Write an equation for this reaction


glutamic acid is

h2nch(ch2ch2cooh)cooh

tollens reagent, formed by NaOH and AgNO3 with NH3

the product would be ethanoic acid and nh3+ch2ch3

very hard

I will ask again.... What is the reagent and the observation that can distinguish between a ketone and an aldehyde?

Good and the observation?

ch3conhch3 + ch3ooh

why is it slow

h2nch(ch2ch2cooh)cooh + 2ch3ch2oh --> h2nch(ch2chcooch2ch3)cooch2ch3 + 2h20 ?

how did you use your knowledge to get

CH3CONHCH3?

You can either use 2,4-DNP to form an orange precipitate, filter, recrystallize, melt, and compare melting points to known values, OR you can use Tollen's Reagent - forms a silver-grey precipitate/mirror if added to an aldehyde, as it is a weak oxidising agent.

SILVER MIRROR for aldehydes, no reaction for ketones

no reaction for alcohols because it is not a strong enough oxidising agent, we actually tried to do it in a chemistry lesson in school it did not work

how did you use your knowledge to get

CH3CONHCH3?

Correct!

Oh yeah just to confirm, is the difference between a peptide and amide link just that a peptide link involves AMINO ACIDS ONLY whereas amide link is just reaction of COOH and NH2??

CH3COO- and CH3NH2, is like forming a peptide bond, CH3COOH is like always a side product in anhydride reactions