Question- The second step is a name reaction. a) What is its name: b) Is it…

Question-
The second step is a name reaction. a) What is its name:
b) Is it OK that we left the reaction in our drawer over the
week? What would have happened if we didn’t have a good seal on the
stopper? Draw a possible reaction scheme.
Background
The field of medicinal chemistry combines the specialties of
synthetic organic chemistry and biology, and biochemistry.
Compounds are generated and biological activity is screened using
target specific assays. . These assays are commonly cellular. To
identify drugs that produce biological activity,
high-throughput-screening campains are commonly employed. Molecules
that produce a response improved through iterative processes.. In
some instances compounds are isolated from natural sources e.g.
Taxol, and synthetic modifications can be performed to improve
efficacy.. In practice, the iterative process is as follows: a
positive screening result justifies the synthesisof a library of
structural analogues to see if a change in substructure leads to
increased potency in the standardized assay.. In concert, DMPK
(Drug metabolism and pharmacokinetics) assays are run to test the
ability of the drug canadite to withhold stresses like oxidation by
a range of cytochrome P450 enzymes. The more reactive the drug is
to these types of assays, the faster it is metabolized. Fast
metabalizom leads to shorter half lives in the body. Candadets of
interest can also be run in animal models at any point. For
neourscience aplications, it is common to quantify the amount of
the drug that has passed through the blood- brain barrier by
decapitating the dosed rats and quantifying the amount of drug in
the pulverized head. For antidepressants, a number of tests can be
performed e.g. the forced swim test. Toxicity studys are run on the
promising canadite(s). With these canadites, larger animal models
are used. These can include dogs, pigs, and monkeys to name a few
common ones.
Acetaminophen, the major ingredient in the NSAID Tylenol, is
readily accessible by the reaction of p-aminophenol and acetic
anhydride following the first reaction in the scheme above. An
effective structural analogue of acetaminophen is phenacetin, a
component of several headache and cold medicines. Phenacetin is
produced by converting the hydroxyl group of acetaminophen to an
ether group by a Williamson Ether reaction as shown in reaction 2
in the scheme above. Experiment 4 provides an opportunity to
synthesize, purify, and analyze acetaminophen and phenacetin.
Reaction 1 – Acetylation of an Aminophenol
To a 10 mL round-bottomed flask equipped with a magnetic stir
bar, add 1.1 g of your assigned aminophenol and 3.0 mL of water.
Carefully add 1.2 mL of acetic anhydride and stir vigorously a hot
water bath. Continue stirring until the solid has completely
dissolved which should take
approximately 10 minutes. Remove the flask from the hot water
bath and allow the reaction to come to room temperature on the
benchtop. Place the flask in an ice bath to complete the cooling
process. Set up a vacuum filtration to isolate the precipitated
product, using a minimum amount of cold water to wash the solid.
Keep the solid on the vacuum filter for ~10 minutes to complete the
drying process. Weigh the crude product and record the mass. Purify
the crude product by recrystallization using water as the solvent.
Repeat the vacuum filtration process to isolate the pure acetylated
aminophenol product and measure a final mass. Obtain an IR, 1H NMR,
and melting point for the product.
Reaction 2 – Williamson Ether Synthesis of an Acetylated
Aminophenol
To a clean and tared 25 mL round-bottomed flask, carefully add
~160 mg of solid sodium. Use extreme caution when handling
the sodium pieces as they readily react with water. Be sure to use
gloves and keep away from all sources of water. Set-up a
water cooled reflux condenser equipped with a CaCl2 drying tube.
Add 4.0 mL of absolute ethanol through the top of the reflux
condenser and quickly place the drying tube on top again. The
sodium/ethanol reaction should happen very quickly with all of the
sodium dissolving. If solid does remain in the flask, place the
reaction on a steam bath to promote dissolving. Bring the reaction
to room temperature and add a predetermined mass ~1.0 g of your
acetylated aminophenol to the flask. Carefully obtain and add 0.8
mL of ethyl iodide to the reaction flask. Use extreme
caution when adding the ethyl iodide as it is a powerful alkylating
agent. Be sure to use gloves when adding to the reaction and work
in the hood for the addition. Return the reaction to the
lab bench and reflux the reaction for 45 minutes using a steam
bath. Quench the reaction with 10 mL of water added through the top
of the condenser. Remove the apparatus from the steam bath and cool
the reaction to room temperature. Complete the cooling process by
immersing the flask in an ice bath. Collect the resulting product
via vacuum filtration and wash the crystals with a minimum amount
of cold water. Purify the crystals by recrystallization using
ethanol as the solvent. Repeat the vacuum filtration process to
collect the pure product and measure a final mass. Obtain an IR, 1H
NMR, and melting point of your pure product.