Write Newman projections for all three staggered conformations of (R)-2-bromobutane, viewing down the C2-C3 bond. Upon treatment with strong base (e.g., NaOH), three alkene isomers can form. Illustrate which of the above conformations would be expected to lead to two of these isomers, each with a double bond between C2 and C3. Predict which will be the major product and explain why.

Provide the systematic name for each of the following isomeric esters with the chemical formula C-H₁2O₂. (Be sure to indicate double bond stereochemistry using (E)/(Z) notation. Indicate stereochemistry in rings with the terms cis or trans. It is not necessary to use italics in writing compound names.) ball & stick - + labels ball & stick- + labels ball & stick + labels 12

Provide an IUPAC name for each of the compounds shown. (Specify (E) (Z) stereochemistry, if relevant, for straight chain alkenes only. Pay attention to commas, dashes, etc.) CH3 CH3 1.) -CH2CH3 CH2CH3 2.)

Draw a structural formula for the more stable carbocation intermediate formed in the reaction shown. CH3CH₂ H H c=c" cms CH3 CH₂CCH3 CH3 + HBr • You do not have to consider stereochemistry. . Do not include anionic counter-ions, e.g., I, in your answer. • For cases in which carbocations of the same or similar stability are expected, draw all of the structures. • Draw one structure per sketcher. Add additional sketchers using the drop-down menu in the bottom right corner. Separate structures with + signs from the drop-down menu.