(2R,3S)-2-Bromo-3-phenylbutane undergoes an E2 elimination when treated with sodium methoxide. Draw all possible Newman projections for the bond relevant for the elimination reaction, and use those Newman projections to explain the stereochemical outcome of the reaction. Draw the final product and provide its IUPAC name.

The southern pine beetle utilizes a multi-component aggregation pheromone (one component shown below) to start mass colonization of healthy trees. The biosynthetic pathway involves the cyclization of this acetal from the straight chain structure. Draw the straight chain structure that could be used to form this acetal. Use wedges and dashes to correctly depict the stereochemistry. H3C- OH ✔

Treatment of the following stereoisomer of 1-bromo-1,2- diphenylpropane with sodium ethoxide in ethanol gives a single stereoisomer of 1,2-diphenylpropene. H3C H C6H5 H C6H5 Br ***I CH3CH₂O Na+ Draw the E2 elimination product of the reaction. Take into account that the starting stereochemistry affects the resulting double bond stereochemistry. CH₂CH₂OH Consider E/Z stereochemistry of alkenes. Do not show stereochemistry in other cases. • You do not have to explicitly draw H atoms. • In cases where there is more than one answer, just draw one. Sn [F ?

The following compound reacts with NaOMe in an SN2 reaction. Draw the transition state and the final product of the reaction and use the transition state geometry to explain the stereochemical outcome of the reaction. What is the side-reaction that might occur and what would be the major product of that reaction? Br NaOMe ČH3