N,N-diethyl-m-toluamide (DEET) is the active ingredient in many insect repellent preparations. Following is one of the steps in its synthesis. In the box below draw the structure of the product of this reaction. H3C MgBr 1. CO2 2. H3O+ product • You do not have to consider stereochemistry. • You do not have to explicitly draw H atoms. • Do not include lone pairs in your answer. They will not be considered in the grading. • Draw the Grignard reagent as a covalent magnesium bromide. 90-87 0 + 11 ? n [

Consider the reaction of 1-butanol with PBr3. Draw the structure of the major organic product. ● ● ● You do not have to consider stereochemistry. You do not have to explicitly draw H atoms. Do not include counter-ions, e.g., Na+, I-, in your answer. If the given reaction has more than one step, give only the final product. If no reaction occurs, draw the organic starting material. Sn [F ? ChemDoodleⓇ

Draw all the isomers of C5H₁0. Clearly show stereochemistry if stereoisomers are possible. Step 1: Start by drawing all the isomers with double bonds. • Consider constitutional isomers, then stereoisomers. Step 2: Draw all isomers containing a ring. • Consider constitutional isomers, then stereoisomers. Step 2: Next consider isomers containing a ring. The largest ring possible with this molecular formula contains 5 carbons, while the smallest possible ring contains 3 carbons. Draw an isomer containing a 5-carbon ring. Rings More Select Draw / C H Erase Consider a 4-carbon ring of C5H₁0. Draw stereoisomers, if applicable. Select Draw Rings More C H Erase

Ignoring stereochemistry, draw the alkylborane formed from the addition of one equivalent of BH3 to the alkene. The alkylborane formed in Part 1 is further treated with H2O2 and HO−. Draw the two stereoisomers of the final product of the reaction. Include stereochemistry where relevant. How many stereocenters are formed from the reaction?    What is the relationship between the stereoisomers?