Propose a complete curved-arrow mechanism for the formation of the fragrant terpene shown below from farnesyl pyrophosphate. Show all cationic intermediates as discrete steps. You do not need to account for the observed stereochemistry. Your mechanism should require no more than three carbocationic shifts. Numbering your carbons will be helpful. farnesyl pyrophosphate OPP Fragrant Terpene

Show how you would prepare monodeuteriocyclopentane (C5H9D) from bromocyclopentane (C5H9Br) using an organometallic reagent.

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 ?