Written Assignment #5
This assignment is worth a possible total of 100 points. Place your answer in the space provided. Remember that in the problems you must show ALL your work in writing in order to receivefull creditfor the answers in Part Ill. Read the “Guidelines” [course syllabus] for further information on what is needed to show your work. No late papers are accepted except by previous arrangement with the instructor.
PARTI – True/False – Circle your response. (4 each , 20 total)
1. Alcohols have both a hydrophilic region and a hydrophobic region, which is a major factor in solubility characteristics. True False 2. In an organometallic compound, the carbon bonded to the metal is electrophilic.
True False 3. Hydride reagents are unusual because the hydrogen has a partial negative charge and is a nucleophile. True False 4. Infrared spectroscopy gives information about individual carbon bonding and the groups that are attached to the carbon. True False 5. primary alcohols make a good starting material in synthesizing alkenes by dehydration, compared to tertiary alcohols. True False
PAR T Il – Multiple Choice – Circle your response. (6 each, 18 total)
Note that some questions may require more than one choice to be a complete
- Choose the product which would result in the following reaction of 2-butanone with the Grignard reagent, followed by protonation: (Note: Only one answer here.)
- Choose the one incorrect statement about IR and NMR spectroscopic analysis.
(A) In both IR and NMR, information is obtained about portions or regions of the structure involving two or more atoms, such as a carbonyl or a methyl group. (B) NMR relates to the energy states of the magnetic spin of a nucleus, which is dependent on the electronic environment around the nucleus.
- Infrared energy values are related to the absorption of energy of the electrons in a given bond to a higher energy state.
- Proton NMR can detect stereoisomeric differences where the protons would have a slightly different chemical (electronic) environment, called diastereotropic protons.
3.) Which of the following alcoholic protons ( O – H) is expected to be the most acidic? (Choose only one answer.)
PART Ill – Written Response (42 total)
This section requires that you SHOW YOUR WORK clearly and legibly in order to be eligible for full credit for each question. Otherwise, you will not receive full credit, even though you have the correct answer, numerically speaking!! !!! [See the “Guidelines” in the course syllabus.]
1.) (12 pts) What products would you expect from the oxidation of these compounds with the reagent specified? Write the structural formula for each product (no need
Reaction with PCC
Starting material hexan- 1-01
2. ) ( 12 pts) In the IR spectrum below,
- identify (label) the peaks corresponding to (i) the C = O stretch, and (ii) the C – H stretch;
- explain what is generally found in the region of 1600 – 1000 cm-I in terms of specific motions, using the terms from the text or the resource on Moodle. Give two specific examples, with a frequency, as found in one of these sources. [See Fig. 12-2, text for an example.]
3000 2000 1000
NIST Chemistry WebBook (https://webbook.nist.gov/chemistry)
- (9 pts) In the I H (proton) NMR spectrum below, identify (label) the protons for (a) the aromatic ring , (b) the -CH3, and (c) the -CH2- attached to the oxygen atom.
5 2 2 2 3
- (9 pts) MRI, (nuclear) magnetic resonance imaging, is an application of proton NMR using two dimensional slices (spectra) of a three-dimensional object, which are then combined into a three-dimensional plot, or image. Describe two specific examples of a diagnosis with this technique, and explain briefly what information can be obtained from proton relaxation times. [See text, Section 13-4, or another source.]
Part IV Technical Response (20 PG)
Read the articles labeled “Start-Ups Nov. 2020” [C&EN, Nov. 16, 2020] [Posted on Moodle]
Answer the following questions using the information provided in this article. You must have legible, complete sentences in order to getfull creditfor a response.
- Give a brief description of the glycoprotein called miraculin, an example of a sweetener found in plants (Joywell Foods). (1-2 sentences)
- Why is it generally not economical to use fruit as a source of sweeteners, and how is Joywell trying to overcome this problem? (2 – 3 sentences)
- RenewC02 is trying to capture and reuse C02. Briefly describe the experimental method they are using, and what the products are. (2 – 3 sentences)
- What is the contribution that Sabinano is making to South Africa, and what is its underlying motivation (besides the products themselves)? (2 -3 sentences)
Synsepalum dulcificum contains a supersweet protein.
o Joywell Foods scales
Joywell was cofounded in 2014 by Jason Ryder, now the company’s chief tech-
up sweet proteins
nology officer. Ryder previously worked at the synthetic-biology firms Amyris
and Bolt Threads. In July, Joywell raised $6.9 million in series A funding led by
Food makers are always on the hunt for
Evolv Ventures, the venture capital fund
better sweeteners—and the supersweet
backed by Kraft Heinz. In addition to
proteins found in plant species like Syn-
building a manufacturing platform, the
sepalum dulcificum could be just the ticket
start-up is working to find out which foods
for ingredients that taste like sugar but are
and beverages taste best when sweetened
healthier and derived from nature. S. dulcificumis also known as miracle
with natural proteins.
fruit thanks to a glycoprotein called miraculin that can make sour, acidic foods
e RenewC02’s catalysts
taste sweet by activating our sweet taste receptors. It’s one of a number of plants
make monomers from
containing proteins that are up to 5,500 times as sweet as sugar, according to Joywell Foods.
C02 and water
But it’s not economical to extract the
At New Jersey-based RenewC02, chemists
sweet proteins from fruit because they are
Anders Laursen and Karin Calvinho are de-
present in tiny amounts. So the Davis, Cal-
veloping electrochemical cells to transform
ifornia-based firm has a plan to produce
carbon dioxide and water into the common
them via fermentation using modified
chemical ethylene glycol and two with mar-
ket potential, methylglyoxal and ftu•andiol.
RenewC02 is developing catalysts for electrochemical cells that convert C02 into useful chemicals.
Electrochemical cells are one way chemists and engineers are seeking to capture C02 and convert it to useful materials, a strategy called carbon capture and use. But the strategy is plagued by low yields and high energy requirements.
To boost the performance of their cells, Laursen and Calvinho are developing catalysts containing nickel phosphides that can reduce C02 to C3 and oxyhydrocarbons at a low electric potential of 10 mV. The core technology came from Rutgers University, where Laursen is a research associate.
In April, RenewC02 secured a $225,000
Phase I business research grant from the US National Science Foundation to develop electrolyzers that convert brine and C02 into ethylene glycol, chlorine, and sodium hydroxide.
o Sabinano provides nanomaterials and expertise to South Africa’s scientists
Nanoscale carbon in forms such as nanotubes, graphene, and doped particles are often at the heart of innovations in batteries, wastewater treatment, lightweight materials, and heat-transfer devices. Now those materials—and the expertise needed to use them—are available to industrial, government, and academic researchers based in South Africa.
Johannesburg-based Sabinano was founded by Sabelo Mhlanga, formerly a materials science professor at the University of South Africa, where he was also deputy director of the school’s Nanotechnology and Water Sustainability Research Unit. Mhlanga became the compapy’s
CEO in 2018.
Sabinano’s offerings span manufacturing, research, consulting, and lab services. Its partners include South Africa’s Industrial Development Corporation and Solzen Energy, a company developing graphene-based ultracapacitors for energy storage.
Selling carbon nanomaterials and offering related services are not Sabinano’s only goals, according to the company’s website: “We would like to see the industry grow in South Africa, through empowering people of all races and backBOMGARDNER