Chemical Forums

Chemistry Forums for Students => High School Chemistry Forum => Chemistry Olympiad and other competitions => Topic started by: Radu on February 10, 2014, 06:02:43 PM

Title: 26th problem IChO - A heterocyclic compound
Post by: Radu on February 10, 2014, 06:02:43 PM
http://icho2014.hus.edu.vn/document/01-24-2014%20IChO46-Preparatory.pdf

      My question is regarding 26.3 . I have to obtain compound C starting from levulic acid. You have my work attached, I simply cannot figure out the role of m-NO2-C6H4-SO3Na in this synthesis.
Title: Re: 26th problem IChO - A heterocyclic compound
Post by: Leroi on April 01, 2014, 03:06:53 PM
i used it as base, even though it's a poor one... Please tell me whether the use of piperidine as condensation catalyst asks for caution because of the carboxylic group or you may simply mix PhCHO, levulic acid and piperidine in a flask, waiting for the reaction to take place
Title: Re: 26th problem IChO - A heterocyclic compound
Post by: Radu on April 02, 2014, 07:30:58 AM
 Humm, I really don't think that amidic nitrogen can be alkylated, especially with such a weak base. If I am to use it as a weak base, I'd use it with hydrazine, to react with that acid chloride. ( a weak base is required, we have a carbonyl group that must be protected).
Title: Re: 26th problem IChO - A heterocyclic compound
Post by: Guvanch on April 06, 2014, 07:54:12 AM
will you participate 46th icho.
Title: Re: 26th problem IChO - A heterocyclic compound
Post by: momoho on April 07, 2014, 01:49:05 PM
Quote from: Radu on February 10, 2014, 06:02:43 PM
http://icho2014.hus.edu.vn/document/01-24-2014%20IChO46-Preparatory.pdf

      My question is regarding 26.3 . I have to obtain compound C starting from levulic acid. You have my work attached, I simply cannot figure out the role of m-NO2-C6H4-SO3Na in this synthesis.
Hi
I am beginner in chemistry...so i will glad to see your answer to question number 25 (cefalotin) if U solve it?
Can i have your answer to this problem?
Title: Re: 26th problem IChO - A heterocyclic compound
Post by: Rutherford on April 22, 2014, 03:46:15 PM
Did anyone figure out the role of m-NO2-C6H4-SO3Na?