1.In today experiment you willperform the aldol condensation between benzaldehyde (PhCHO) andacetone to synthesize dibenzalacetone. Answer the followingquestions regarding this reaction:

a.This reaction is an example of amixed aldol condensation. Why is only one product formed and nomixture of compounds are obtained like in other aldolcondensations? (Hint: Benzaldehyde cannot undergo“ALDOL” reaction by itself in presence of strong base (NaOH).Why?)

b.Look at the mmols of the reagentsused in this reaction and specify the limiting reagent.

c.Explain why the NaOH is a catalystin this reaction, rather than a reagent. (Hint - look at thereaction mechanism.)

d.Usually an aldol condensation mustbe heated in order to dehydrate the beta-hydroxy ketone to form theC=C. What is different about this product that causes it todehydrate at room temperature?

e.Why does this product have a yellowcolor?

f.The IR spectrum of dibenzalacetoneshows the C=O peak at lower wavenumbers (1639 cm^-1) thanstandard C=O frequency (1715 cm^-1)? Why do youthink?

g. How would you change the proceduresin this experiment if you wished to synthesize benzalacetone,C₆H₅CH=CHCOCH₃?Benzalacetophenone,C₆H₅CH=CHCOC₆H₅?

h.The name dibenzalacetone does notcompletely characterize the molecules made in this experiment.There are 3 isomeric dibenzalacetones, one melting at 100-110°_max 330 nm,34,300; another melting at 60 °C,_max= 295 nm20,000; and a third, a liquidwith_max= 287 nm Draw the structures of the threegeometric isomers of dibenzalacetone (Z,Z; Z,E;E,E), and assign each one to the three molecules described inthe previous paragraph.

i.Write the detailed mechanism for theformation of dibenzalacetone from benzalacetone andbenzaldehyde.