Question

I. 1,4-hexadiene II. 1,3,5-octatriene III. 3,4-dimethyl-2,4-hexadiene.

(A) Draw the structures of the above compounds and circle the compound with the highest lmax in UV-Vis spectrum.

(B) Draw the s-cis and s-trans isomers for the hexadiene compound(s) that will have the highest lmax in UV-Vis spectrum (I or III?).

(C) Draw the structure of the major product which results when compound III is treated with: (1) HBr at -80 oC.

(2) HBr at 40 oC.
What type of control does each of these reactions have (kinetic vs. thermodynamic)?

(D) Write the structure(s) of the compounds formed when the 2 isomers of 3,4-dimethyl-2,4-hexadiene (s-cis and s-trans) are reacted with cis-1,2-dicyanoethylene (NCCH=CHCN). What type of reaction is observed

Answer 1