I. (32 points) Name. Page 1. (ii) its diastereomer its structural isomer its enantiomer. The product you have drawn will. H 3 CO Cl form with H 3 CO

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Clifford Lambert
5 years ago
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1 ame. ( points) Page Each of the reactions yields a PAR of main organic products, but you should only draw one. Then answer the other questions about the starting and the products formed. Check boxes are only given credit if product is correct (i) (ii) C C starting /C R C C also this pair! heated P (iii) same R (iv) (v) Provide the complete name (including stereochemical labels as needed) for this starting - pts per error - numbering is one error,,-trimethylcyclopent--en--ol (vi) Fill in the predicted number of MR signals expected for the starting : C-MR 5 Check boxes are only given credit if product is correct starting KMn (i) R (ii) Pd (iii) R (iv) (v) Provide the complete name (including stereochemical labels as needed) for this starting - pts per error - numbering is one error or -,-diethyl--cyclohexene -,-diethylcyclohex--ene ignore any double bond stereochemistry (vi) Fill in the predicted number of MR signals expected for the starting : C-MR 0

2 . (7 points) ame Page Selection is everywhere. Each of the following transformations exhibits some kind of selection. Provide the required missing s, either starting s, products, or complete transformations. (i) Draw the alkene starting a s C C C one product (i) Draw one product Despite containing two potential leaving groups, the reaction shown below yields one organic elimination product. Explain this regioselection by showing the conformation (chair) of the starting that undergoes this E reaction; draw the product, too. (ii) This product forms: with with alone (ii) This product forms: with with alone (i) chair conformation favored for E reaction (ii) kinetically favored product E a if other conformer (t-bu axial +) if wrong molecule in any way no pts errors in bond angles - per erro D. The following transformation occur in three steps, starting with the formation of an iodonium ion intermediate and ending with deprotonation, yielding a neutral organic product. gnoring stereochemistry, draw a complete curved arrow mechanism for the formation of this product. (i) Show the curved arrow mechanism for the first step (ii) Draw all products and show the curved arrow mechanism for the second step (iii) Draw all products and show the curved arrow mechanism for the third step B return arrow can go to either C of the pi bond pts intermediate (all or nothing with charge) points for each mechanism - no partial, all arrows 0

3 ame. ( points) Page ne starting undergoes two different transformations in each of these problems. Please draw all main organic products, clearly showing in your drawing all structural and/or stereochemical information as needed; restrict your answers to major regioisomers when regioselection is predicted, assume no rearrangement occurs, and ignore all reaction byproducts unless instructed otherwise. (a) Draw product(s) (b) Draw product(s) (+) α-phellandrene must show D... a flavoring must show D... and s might be drawn in Pd/C excess ) ) Zn excess (a) Balance your reactions organic must be correct to get points for balancing(b) Balance your reactions ) ) a S C a or a + - S ) C ) S - if draw both, only pt (a) Draw product(s) C C C C C C C C C (b) Draw C 8 product(s) all = pts - for each missing one (means first is worth ) C C C heat C C C C C C C (a) Draw product(s) C C C C ) B ) /a C C (b) Draw product(s) C C C C C C C carene the pungent odor of turpentine C C

4 V. (5 points) ame Page Supply the missing information. f any reaction yields more than one product, draw one and write "+ enantiomer" or "+ diastereomer" in the box. f you are supplying reagents and a multistep transformation is required, be sure to number your steps appropriately. equivalents of this product form Pd/BaS Pb Zn draw each product in the appropriate box C-MR shows signals C-MR shows signals graded step by step pt each only forward ) S C C ) a ) ac (any or no spectator) only this product is formed C 5 equivalent organic must be correct to get points for byproducts ) a equivalent draw all products a ) C C D. must be D + / + enantiomer /Pt

5 V. ( points) Analyze the compounds shown below. ame Page 5 Compound Compound This drawing represents (fill in a number for each box) This drawing represents (fill in a number for each box) distinct molecule(s) distinct molecule(s) chiral molecule(s) When Compound is treated with mildly acidic conditions, a single molecular rearrangement step results in the dehydration product, Compound. Show the complete multi-step mechanism for the formation of. You should show and use the best resonance contributor for any intermediate in your mechanism. Choose your acid/conjugate base wisely. gnore stereochemistry. 0 chiral molecule(s) Compound Compound pts each intermediate pts each mechanistic step (must choose correct acid/base) grading stops with first irrational step only the major resonance must be shown Under these same conditions, another dehydration product is also formed, again explained by a single rearrangement step. Predict the structure of Compound 8 Compound, a structural isomer of Compound Compound

1.5 h; 140 points please print clearly Dr. Ginger Shultz Dr. Kathleen Nolta. Problem Points Score GSI I 32 II 27 III 32 IV 25 V 24 Total 140

1.5 h; 140 points please print clearly Dr. Ginger Shultz Dr. Kathleen Nolta. Problem Points Score GSI I 32 II 27 III 32 IV 25 V 24 Total 140 hemistry 10 Third Examination First ame Last ame 1.5 h; 10 points please print clearly Dr. Ginger hultz Dr. Kathleen olta ignature UM D # PRT TE FRT LETTER F YUR LAT AME ERE: Problem Points core G 7 V