These are the homework exercises to accompany the Textmap for McMurry's Organic Chemistry textbook.
A sample with a concentration of 0.3 g/mL was placed in a cell with a length of 5 cm. The resulting rotation at the sodium D line was +1.52°. What is the [α]D?
5 cm = 0.5 dm
[α]D = α/(c x l) = +1.52/(0.3 x 0.5) = +10.1°
Orient the following so that the least priority (4) atom is paced behind, then assign stereochemistry (R or S).
Assign R/S to the following molecule.
A = S; B = R
The stereo center is R.
Determine the stereochemistry of the following molecule:
Which of the following are meso-compounds:
C – 2,3-dibromobutane
D – 2,3-dibromopentane
Compounds A and C are meso.
What kind of isomers are the following pairs:
A – (R)-5-chlorohexene and 6-chlorohexene
B – (2R,3R)-dibromohexane and (2R,3S)-dibromohexane
A = Structural Isomers
B = Diastereomers
State which of the following hydrogen atoms are pro-R or pro-S.
Identify which side is Re or Si
Left compound: Ha = pro-S and Hb = pro-R
Right compound: Ha = pro-R and Hb = pro-S
A – Re; B – Si; C – Re; D – Si
Draw the two enantiomeric forms of 2-butanol, CH3CH(OH)CH2CH3. Label their configurations.
Sometimes, compounds have many chiral centers in them. For the following compounds, identify four chiral centers in each, mark them with asterisks, and identify each center as R or S configuration.
The following is the structure of dysinosin A, a potent thrombin inhibitor that consequently prevents blood clotting.
Ginkgolide B (below) is a secondary metabolite of the ginkgo tree, extracts of which are used in Chinese medicine.
Sanglifehrin A, shown below, is produced by a bacteria that may be found in the soil of coffee plantations in Malawi. It is also a promising candidate for the treatment of organ transplant patients owing to its potent immuno-suppressant activity.