Question

ANSWERS ALREADY PROVIDED!

1) just need an explanation as to how to go about the biodiesel rxn and how to determine the product.

2)also, for the reactions. just briefly describe in each step what type of rxn it is and how we arrive at that answer. studying for exam so any kind of explanation will help. thank you!

3. (9 pts) A) Draw the products of the biodiesel reaction below: at CH-он, н- meaRn mco OH

   =1

2=

Answer 1

Answer 1) Biodiesel contain triglycerides of different fatty acid. The reaction shown below is a simple acid hydrolysis of triglycerides. Which produces glycerol and long chain carboxylic acid. These carboxylic acid in presence of alcohol (CH₃OH or MeOH) undergoes acid catalyzed esterification to give simple esters as shown in the given product. (We can split up the reaction in two steps as given below). Therefore the overall reaction can be termed as transesterification of biodiesel.

он н* нус нс-он + но нсон снзон Насот

Answer 2: The first step is acetal hydrolysis in presence of acid (the given compound 1,1-dimethoxy-2-methyl-propane is also known as acetal). An acetal is a functional group with the connectivity RHC(OR')₂). Acetals are formed from and convertible to aldehydes or ketones. (The reaction 1 below may be help to understand the underlying principle). Second step is oxidation of aldehyde in presence of chromic acid which results in the formation of carboxylic acid. Next is acid catalysis esterification of carboxylic acid in the presence on an alcohol. Further is a tranesterification reaction as shown in above problem. Transesterification is the process of exchanging the organic group R of an ester with the organic group R of an alcohol. Therefore one type of ester gets converted to another type of ester as shown in the reaction. The last step is base hydrolysis of ester in the presence of NaOH which results in the formation of sodium salt of the corresponding carboxylic acid and alcohol.

R'OH R'OH HROR ROH HOR HOR In the given problem R = OMe Given acetal is = OMe 1,1-dimethoxy-2- methylpropane