IMG_NEW_0020 - a b\P1 RL 1 t r:ffi*r'1 t-W!1'T I hOfu*l t...

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CHEM 28I Tutorial Problem Set No. 4 l. In class it was mentioned that E and Z isomers of alkenes have a barrier to interconversion of approximately 63 kcal/mol and, consequently, can be considered configurationally stable. However, in biological systems the isomerizatton (or EIZ interconversion) of alkenes may occur readily and plays an important role in many biological processes. Can you briefly describe the Z to E interconversion of Z-retinal and what role this plays in our ability to see? 2. Please name the following molecules and draw them in their most stable (chair) conformations. Highlight steric interactions (if any) in this conformation. This should be useful practice for you as this type of question caused the most difficulties
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