Organic Chemistry

  Organic Chemistry   1. Circle every chiral center in the following structure. If the structure does not have any chiral centers, write “achiral” as your answer. Hint: use your model set to help you find any chiral centers. 2. Calculate the specific rotation, [α]D, for the following data: αobs = –13.5o , l = 150 mm, Conc. = 0.75 g/liter. 3. How are (+), (–), d, l, R, and S different from each other? 4. Assign the R/S configuration for each chiral center in the following structure. Hint: use your model set to build the structure so that you can more easily determine the configuration(s). 5. What is the IUPAC name of the compound in question 4 if the prefix names for the halide and the alcohol are fluoro- and hydroxy-, respectively. 6. Draw the structure of (3S,4R)-4-isopropyl-3-methyloctane. Hint: use your model set to build the structure so that you can more easily determine the configurations at carbons 3 and 4. 7. How are meso compounds, diastereomeric compounds, and enantiomeric compounds different from each other? 8. For the following pair of compounds, indicate whether they are enantiomers, diastereomers, meso, or identical compounds. Hint: yes, you guessed it...use your model set! 9. Define the term racemic mixture. 10. Briefly describe how the enantiomers of a racemic mixture can be resolved. 11. Consider the statement “cis-1,2-disubstituted cyclohexanes are always meso, but trans-1,2-disubstituted cyclohexanes are never meso”. Is this a true statement? Please explain your answer. (And the hint will be...use your model set. Did you get the idea that model sets come in handy for this chapter?) 12. For each compound below, assign Re or Si to the side that faces you. a. b. 13. Assign pro-R or pro-S for each indicated hydrogen in the structure