(c) Is this the form of MDPV that you would expect to exist in the bloodstream, where the ph is ~7? Why or why not?

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Dana Copeland
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1 I. ( points) ame Page 1 Methylenedioxypyrovalerone (MDPV) is one terribly dangerous ingredient in the recreational drugs better known as "bath salts." This psychoactive drug acts as a stimulant with dangerous, often violent, effects. (a) Draw a circle around the shortest carbon-oxygen bond in MDPV. atom 1 (b) For each of the atoms indicated with an arrow, provide the atom's most reasonable hybridization as well as its electronic geometry (VSEPR) and observable geometry (write none if it is not observable). Be careful to consider appropriate bond angles in small rings. atom hybridization electronic geometry observable geometry atom Methylenedioxypyrovalerone (MDPV) atom 1 atom atom (c) Is this the form of MDPV that you would expect to exist in the bloodstream, where the p is ~7? Why or why not? (d) Molecule 1 is a fragment of methylenedioxypyrovalerone. Draw the single best resonance form of 1 that has all closed-shell atoms and formal charges of -1, 0, or 1 on all atoms. As always, you should remember that linear atoms (sp hybridization) are not expected in rings of this size. 1 Draw the best all closed-shell resonance form Alprazolam, trade name Xanax, is the benzodiazepine drug that is often used to counteract the stimulant shown above. (e) For each of the atoms indicated with an arrow, provide the atom atom's most reasonable hybridization as well as its electronic atom geometry (VSEPR) and observable geometry (write none if it is not observable). Bond Bond 1 atom atom atom l hybridization electronic geometry observable geometry (f) Place Bonds 1- in order from shortest to longest, as predicted by considering resonance, hybridization, etc. If any bonds are predicted to be the same length, circle them in your response below. l atom l Bond Bond shortest longest alprazolam

2 II. (1 points) A. ame Page (a) xalic acid is a dicarboxylic acid with pka's of 1.5 and.. It is used by some beekeepers in order to protect their bees from mites. When it is suspended in water at a p of., two forms of this compound exist. Draw both of these forms and circle the one that is expected to be present in a higher concentration. oxalic acid (b) The first proton to come off of oxalic acid has a lower pka than expected for a carboxylic acid. It has been suggested that the conjugate base (mono-protonated form of oxalic acid) is stabilized by an intramolecular (within the same molecule) hydrogen bond. Draw the (mono-protonated) conjugate base, and show this intramolecular hydrogen bond that can explain its stability. mono-protonated form, showing intramolecular -bond 5 (c) Draw a structural isomer of oxalic acid,, that: - contains only uncharged atoms - contains a ring - contains no hydrogen bonding donor groups (d) Provide the missing information for the proton transfer reaction that is most likely to occur. Always draw the most significant resonance contributor when more than one is possible. Be sure to balance your reaction and evaluate the Keq as indicated. provide the products for the most likely reaction complete the expression for Keq K K eq = 10 B. Despite its bad reputation as a poison, the element arsenic can be found in a wide variety of organic compounds, like cacodylic acid. acodylic acid is As a weak acid that is often used in the staining of biological samples for better cacodylic acid microscopic viewing. Using the pka information for oxalic acid given above, provide the missing information for the following proton transfer reactions. Be sure to balance your reactions. a As (a) what is the pka for cacodylic acid? (b) K eq = 10 -

3 A. III. (17 points) ame Page (a) itrinin is a mycotoxin that is being investigated as a possible cause of yellow rice fever. Draw the single best resonance contributor for citrinin (all atoms closed shell, all atomic formal charges of 1, 0, or -1). itrinin - one resonance form itrinin - best resonance form (b) itrinin is a onsted acid whose most acidic proton has a pka of ~.5. ircle the bases in the box that can deprotonate citrinin with a K eq > 10. Li K B. onsider Molecule below. ompare the structure of this molecule to the other drawings and pick the best description for their relations. (a) (b) (c) compared to, this is: compared to, this is: compared to, this is: the same resonance form for the same resonance form for the same resonance form for a different resonance form for a structural isomer of a conjugate acid of a different resonance form for a structural isomer of a conjugate acid of a different resonance form for a structural isomer of a conjugate acid of a conjugate base of a conjugate base of a conjugate base of (d) Draw a structural isomer (complete Lewis structure) of that contains - all closed shell atoms - a 5-atom ring - only one hydrogen bond donor - only atoms that carry no formal charge

4 IV. ( points) ame Page (a) Methyl--cyanoacrylate, better known as "Super Glue," has found many useful applications, especially in forensic science. Super Glue is produced in a relatively simple synthesis involving acid/base chemistry and a condensation between Molecules and, indicated below. Provide the missing information for each step in this synthesis. Remember to use the curved arrow notation accurately and efficiently. provide the curved arrow mechanism for the proton transfer B Int-A B Draw the products of the condensation step, and the curved arrow mechanism for the formation of the final product the condensation step methyl--cyanoacrylate (b) The intermediate that forms during this reaction, "Int-A", is interesting in itself. i) Assess bond angles and geometries for the atoms indicated in this compound. ii)draw two other significant resonance contributors for this compound, each containing only one atom with a formal charge; make sure all atoms are closed shell, and atomic formal charges are 1, 0, or -1. two other resonance contributors for Int-A containing only one charged atom Int-A (c) Provide an accurate and complete three-dimensional orbital picture for the most significant resonance contributor for Int-A. You should use lines, dashes, wedges, and p orbitals (lone or overlapping) to show the direction of all electrons (or empty orbitals) in your drawing. All bond angles should reflect the appropriate geometry and hybridization chosen for your drawing. You may abbreviate the methyl group as -. 8

5 V. (1 points) ame Page 5 (a) Titanium tetrachloride (Til, nicknamed "tickle") is a volatile metal halide that is essential for the production of titanium metal. As with other transition metals, like Al and Fe, titanium is a strong Lewis acid. Provide the missing information for each of the following complexation reactions; be sure to draw the best resonance contributor if more than one is possible. l l Ti l l (b) Methyl acetate is often used as a solvent in glues and varnishes. It is very reactive as a base, and the product(s) of the following reaction can be predicted if you consider resonance carefully. Draw the product(s). B methyl acetate (c) Draw a simple D orbital picture of methyl acetate, considering all major resonance contributors when assessing geometry (the major resonance form is shown). You should use lines, dashes, wedges, and p orbitals (lone or overlapping) to show the direction of all electrons (or empty orbitals) in your drawing. All bond angles should reflect the appropriate geometry and hybridization chosen for your drawing. methyl acetate (d) ircle all the acids that could be used to protonate the most basic site on Molecule 5 successfully (K eq > 1), without protonating the second site successfully (assuming that the acid is available in excess amounts). S l 5 l F

sp 2 sp 2 trigonal planar bent 2

sp 2 sp 2 trigonal planar bent 2 I. ( points) ame Page 1 Methylenedioxypyrovalerone (MDPV) is one terribly dangerous ingredient in the recreational drugs better known as "bath salts." This psychoactive drug acts as a stimulant with dangerous,