Thanks
 
 


I would like to thank the iut A of Lille, for giving me the chance and the opportunity to do my internship in Japan.
 


I also wish to thank Mr. Yamada, director of the establishment, for welcoming me during these three months. I also thank the staff of the dormitory and the canteen.
 


I thank Mr. Yokoyama, my teacher training who have been very helpful to get familiar with the japans methods work.
 


I would also like to thank Walter and Daouda, two foreign students who allowed me to adapt me in smoothly.
 


And finally, I thank all my teachers in France and Japan, and all people who help me for my internship. 


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Summary
 
 


Introduction
 


I-Japan 
 1-History
 2-Culture 
 3-Geography 


II-Akita
 1- Akita city
 2- Akita National College of technology
 


III-My studies
 1-New deprotection method of the Troc group with (Bu3Sn)2 under microwave
 a) Why a new study?
 b) Research on the new method
 c) Application on a synthesis


2- Study of the selective protection for the hydroxyl group in diol
 a) Why this study?
 b) Experiment
 c) Result and comparison
 
 


Conclusion 
 


Annex
 


A1-What is it the Troc group?
 A2 -Hydroxyl group and his protecting groups
 A3- Micro-wave
 A4- Hiragana, Katakana, kanji


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Introduction
 


In continuation of my training in the second year of DUT chemistry, he was offered to me to do my internship abroad, especially in Japan. During these three months, I discovered a fascinating country where respect, courtesy, friendliness, helpfulness and thoroughness of work are educated from childhood. The Japanese life has managed to grow while keeping their traditions and life principles found in everyday life but also at work. 
 During these three months I rubbed the Japanese in their everyday life, so I could learn how they live and work. Throughout the internship, I investigated two studies: analysis a synthesis of a reaction to ScienceDirect.com and a study of selective protection. This allowed me to see and get used to their methods of work.
 Indeed, since some around ten years, the protection of certain chemical groups is essential for some reactions and allowed the researchers to discover new methods and new compounds. Today the search for such protective elements is vast and very important in the chemical domain, it would be necessary almost found a method for every reaction. It is for that reason that my professor asked me to study at first how the chemists proceed, using a reaction published on sciencedirect.com, and then to make a search myself on the protection of a group hydroxide.
 In training of chemistry but also culturally, I will speak first of Japan and Akita City, then I will explain all of my work in the department of chemistry at the Akita National College technology.
 


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I-Japan 
 


1-History
 


Legend has it that Japan had been founded in the 7th century BC by Emperor Jimmu. The Japanese will be led by high society and then by the shogun. In 1686, Japan isolated from the rest of the world not to undergo the colonization of Western countries. Only two centuries later, on March 31, 1854, Commodore Matthew Perry and the "Black Ships" of the United States Navy forced the opening of Japan to the Outside World with the Convention of Kanagawa and restores the power to the Emperor.
 



 Convention of Kanagawa
 
 


Subsequently, the Japanese began an era of military expansionism which led him to take part in the Second World War and ends at the same time as the war.And now will be under American tutelage.In 1947, Japan adopted a new pacifist constitution emphasizing liberal democratic practices. The Allied occupation ended by the Treaty of San Francisco in 1952 and Japan was granted membership in the United Nations in 1956. Japan later achieved spectacular growth to become the second largest economy in the world, with an annual growth rate averaging 10% for four decades. This ended in the mid-1990s when Japan suffered a major recession. Positive growth in the early twenty-first century has signaled a gradual recovery.


(Skyscraper in Shinjuku, Tokyo)


Today, American influence over the past century is very visible (in sport, the big cities) but you can also see the influence of Western countries like France (Food and especially breakfast).
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2-Culture
 
 a)

Language 
 


The language is spoken mainly in Japan but also in some Japanese emigrant communities around the world. It is an agglutinative language and the sound inventory of Japanese is relatively small but has a lexically distinct pitch-accent system. Japanese is written with a combination of three scripts: hiragana, derived from the Chinese cursive script, katakana, derived as shorthand from Chinese characters, and kanji, imported from China. The Latin alphabet, rōmaji, is also often used in modern Japanese, especially for company names and logos, advertising, and when inputting Japanese into a computer. The Hindu-Arabic numerals are generally used for numbers, but traditional Sino-Japanese numerals are also commonplace. (cf annex 4) 
 
 b)

Food
 


The Japanese food is mainly based on sea food (sushi, maki ) and rice (onigiri , gohan).A standard Japanese meal generally consists of several different okazu accompanying a bowl of cooked white Japanese rice, a bowl of soup and some tsukemono.
 





Tamago kake gohan(left), tsukemono, miso-shiru(miso soup)





Noodles are an essential part of Japanese cuisine usually as an alternative to a rice-based meal as soba, udon and ramen.
 


The Japanese use the famous chopsticks for to eat, called “ashi”.
 
 c)

Some activities





The culture has adapted to Western influences, as shown in the sport where sumo and baseball are the two most popular sports. But also in religion where Shintoism and Buddhism accepts Christianity. We also cited the geisha, the tea ceremony, calligraphy, origami...
 


Wrestling Sumo

Temple of Shintoïsme 





3-Geography
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Japan is a country of over three thousand islands extending along the Pacific coast of Asia. The main islands, running from north to south, are Hokkaidō, Honshu (the main island), Shikoku and Kyushu. The Ryukyu Islands, including Okinawa, are a chain of islands south of Kyushu. Together they are often known as the Japanese Archipelago. About 70% to 80% of the country is forested, mountainous, and unsuitable for agricultural, industrial, or residential use. This is because of the generally steep elevations, climate and risk of landslides caused by earthquakes, soft ground and heavy rain. This has resulted in an extremely high population density in the habitable zones that are mainly located in coastal areas. Japan is one of the most densely populated countries in the world

Map of Japan

Japan consists of forty-seven prefectures, each overseen by an elected governor, legislature and administrative bureaucracy. Each prefecture is further divided into cities, towns and villages.

Akita


For my part, I did my internship in the city of Akita, Prefecture of the region of the same name. (cf number 5 on the map)


II-Akita
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1-Akita city
 Akita (秋田 市, Akita-shi) is the capital of the prefecture of Akita, on the right bank of the river Omono in the Tohoku region. 1 January 2010, the city has a population of 325,905 inhabitants spread over 905.67 km2, a density of 359.85 people per km2.The city officially founded in 1889, but the castle has become the center was founded in 1604. It is for this reason that the city celebrated its 400th anniversary in 2004.
 





Emblem of the city
 
 


Akita is within proximity of the most important oil fields in Japan and near the sea. Today, Akita is an industrial city where sectors such as oil, chemicals, textiles, wood but also fisheries have developed. Akita is also a university town, where there is a public university and a private university: Akita International University, where courses are in English.
 


Akita International University






 


But in Japan, Akita is best known for his Kanto Festival taking place from August 5 to 7. It became the symbol of the city and attracts up to 1.3 million people. A
Kanto
is
an
array
of
many


candle‐lit
lanterns
hung
on
a
bamboo
frame
and
each
one
looks
like
a
glowing
ear
of
rice.
The
 larger
Kanto,
weighing
about
50
kg
(110
lbs.),
rise
12
m
(13.2
yd.)
into
the
air
and
suspend
46
 lanterns.
With
more
than
200
Kantos,
the
number
of
individual
lanterns
reaches
10,000.

 
 
 


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 Kanto festival



 



 Kanto festival

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2- Akita National College of Technology
 


The National College of Technology is a private school, which opened its doors in 1964 under the request of the Japanese government, which offering students four departments: mechanical engineering, electrical and computer engineering, applied chemistry and, civil and environmental engineering. Since 2004 the institute became independent.
 
 
 


Even if it won its independence, its goal to train future engineers has not changed. We can therefore see that the institution offers many ways for students to flourish properly in their work but also in their personal life. 
 


Many club sports such as football, handball, baseball, judo, aikido ... are open to students, but there are also cultural clubs such as tea ceremony, shogi, the igo, the picture ... Thus students have a choice and can unwind after classes. Throughout the year, it is also organized various activities for students in the dormitory. During my three me I could participate in morning football (soccer tournaments between each floor of each dorm), which takes place over two days between 6:00 and 7:20 and the festival of the dormitory where some games are organized, food is sold and the evening barbecue is organized, followed by bingo and karaoke.
 



 





For my part, within the college, I worked in the chemistry laboratory under the tutelage of M. Yokoyama, and I played football and participated tea ceremony with the Japanese in the clubs.


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III-My studies
 


During these three months, I conducted research in the field of organic chemistry, especially in protecting the hydroxyl group. Yokoayama sen-sei (Japanese teacher) asked me first to study and introduce a search ScienceDirect.com, and then I could start my research experiments. So I will present my research in that order.
 


1-New deprotection method of the Troc group with (Bu3Sn)2 under microwave.(Research conducted in 2005 at the University of Osaka by Koichi Fukase and Hiroomi Tokimoto)
 






 a)

Troc group


The 2,2,2-Trichloroethoxycarbonyl call too Troc group has been frequently used for the protection of amino and hydroxyl group in organic synthesis, especially oligosaccharide synthesis. It can be formed from several reactions: 
 -Cl3CCH2OCOCl, Pyr or aq.NaOH, 25°C, 12h
 -Silylate with Me3SiN=C(OSiMe3)CH3 then treat with Cl3CCH2OCOCl
 -Cl3CCH2OCOCl O – succinimidyl, 1N NaOH or 1N Na2CO3, dioxane, 77-96% yield. This method does not result in oligopeptide formation when used to prepare amino acid dérivative
 -Treatment of a tertiary benzylamine also affords the Troc derivative with cleavage of the benzyl group (Cl3CCH2OCOCl, CH3CN, 93% yield)
 


-

, CH2CL2, rt, 35h, 90-97% yield



 





The Troc group is generally removed via a reductive elimination process, such as Zn in AcOH, Zn-Cu in AcOH… or by electrolysis. Most of these methods are carried out under heterogeneous condition and hence are difficult to apply on solid phase synthesis. In addition, we can observed sometimes that significant amount of byproduct, as dichloroethoxycarbonylated, were formed by the cleavage of the Troc group with Zn or Zn-Cu in AcOH.
 
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b)

Microwave


Microwave chemistry is the science of applying microwave irradiation to chemical reactions. Microwaves act as high frequency electric fields and will generally heat any material containing mobile electric charges, such as polar molecules in a solvent or conducting ions in a solid. Polar solvents are heated as their component molecules are forced to rotate with the field and lose energy in collisions. Semiconducting and conducting samples heat when ions or electrons within them form an electric current and energy is lost due to the electrical resistance of the material. Microwave heating in the laboratory began to gain wide acceptance following papers in 1986, although the use of microwave heating in chemical modification can be traced back to the 1950s. Although occasionally known by such acronyms as 'MEC' (Microwave-Enhanced Chemistry) or MORE synthesis (Microwave-organic Reaction Enhancement), these acronyms have had little acceptance outside a small number of groups.
 


Microwave heating is able to heat the target compounds without heating the entire furnace or oil bath, which saves time and energy. It is also able to heat sufficiently thin objects throughout their volume (instead of through its outer surface), in theory producing more uniform heating. However, due to the design of most microwave ovens and to uneven absorption by the object being heated, the microwave field is usually non-uniform and localized superheating occurs. Different compounds convert microwave radiation to heat by different amounts. This selectivity allows some parts of the object being heated to heat more quickly or more slowly than others (particularly the reaction vessel). Microwave heating can have certain benefits over conventional ovens: 

reaction rate acceleration



milder reaction conditions



higher chemical yield



lower energy usage



different reaction selectivities

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Experiment


c) 


The researcher began by trying to find a new solvent to facilitate removal of Troc group by a reductive elimination process, and if possible with little byproduct. 
 They then launched the following reaction:
 
 
 ‐AIBN
(0,1
equiv)
 orBu3SnH
(1,1
equiv)
 or
Et3B
(1
,1
equiv)
 or
(Bu3Sn)2




 








The first two solvents tested were benzene and toluene, but are not persuasive. Cleavage of the Troc group, in these solvent is very slow and gives only a small amount of the desired product. The third test is the solvent DMF, and approved by the researchers. They found is the best choice for a radical cyclization on solid support. 
 


Solvent


Benzene 


Toluene


DMF


Observation


Slow and small amount


Slow and small amout


Good radical cyclisation


Conclusion


Not used


Not used


Best Choice





Surprisingly, the Troc group was removed quantitatively by using (Bu3Sn)2 in DMF without any effect on the allyl group, the compounds then acetylated for easy purification. AIBN and Bu3SnH gave many byproducts in DMF, and Et3B also cleaved the Troc group but afforded the ethyl group adduct to the allyl group.
 


Solvent


DMF


DMF


DMF


DMF


Reagent of the reductive elimination


AIBN


Bu3SnH


Et3B


(Bu3Sn)2


Observation


Many byproduct*


Yields


17%


*including

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Ethyl group Many byproduct*
 adduct to the allyl group
 17%


No data


Any byproduct
 99%


dichloroethoxycarbonylated

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After these experiences, we thus obtain the following reaction:
 





This reaction offers good yields; researchers have tried then to reduce the reaction time by using microwave.





The reaction under microwaves is not altered and the time is greatly reduced. The reaction under microwave also allows us to verify that the choice of the DMF is better than benzene.
 The researchers said:" Probably, Bu3SnCl formed by the reaction was reacted with the tributylstannyl radical to regenerate (Bu3Sn)2 and form a chlorine radical, wich might be reduced by DMF" for to explain us than a small amount of (Bu3Sn)2 was enough to complete the deprotection of the reaction.
 


These results proved that this cleavage of the Troc group is good, so they applied this method on an organic synthesis.


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Applying this method on a solid-phase synthesis.
 
 


‐The
 reaction
 sequence
 began
 withe
 the
 introduction
 of
 linker
 (5)
 to
 aminomethylated
 polystyrene
 by
 amide
bond
formation.
 
 ‐N‐Troc
 glucosamine
 was
 then
 introduced
by
the
trichloroacetimidate
 method.
 
 
 
 ‐Deprotection
 of
 the
 Troc
 group
 using
 the
new
method.
 ‐The
resulting
resin
was
acetylated
and
 cleaved
 by
 NaOMe
 in
 THF/MeOh
 to
 give
 the
 desired
 compound
 (7)
 in
 88%
 for
five
steps.
 





Researchers have established a new method of deprotection of Troc group using Bu3Sn2 in DMF under microwave. This method is fast and gives a good yield.
 
 
 
 


For me this study has allowed me to incorporate some concepts and steps in research to improve an existing reaction. It also allowed me to deepen my knowledge in the field of protecting group chemistry.

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2- Study of the selective protection for the hydroxyl group in diol
 


Since a few protective groups cannot satisfy all criteria for elaborate substrate, a large number of mutually complementary protective groups are needed and, indeed, are available. Now in early syntheses, the chemist has a large choice of protecting group.
 


a) Properties of protection group
 When a chemical reaction is to be carried out selectively at one reactive site in a multifunctional compound, other reactive sites must be temporarily blocked. Many protective groups have been, and are being, developed for this purpose. A protective group must fulfill a number of requirements. It must react selectively in good yield to give a protected substrate that is stable to the projected reactions. The protective group must be selectively removed in good yield by readily available, preferably nontoxic reagents that do not attack the regenerated functional group. The protective group should form a derivate (without the generation of new stereogenic centers) that can easily be separated from side product associated with its formation or cleavage. The protective group should have a minimum of additional functionality to avoid further sites of reaction. All things considered, no protective group is the best protective group. Currently, the science and art of organic synthesis, contrary to the opinion of some, has a long way to go before we can call it a finished and well defined discipline, as is amply illustrated by the extensive use of protective groups during the synthesis of multifunctional molecule. Greater control over the chemistry used in the beautiful and diverse molecular frameworks, as well as unnatural structures, is needed when one considers the number of protection and deprotection steps often used to synthesize a molecule. 


b) Hydroxyl group 
 The term hydroxyl group is used to describe the functional group –OH when it is a substituent in an organic compound. Organic molecules containing a hydroxyl group are known as alcohols (the simplest of which have the formula CnH2n+1–OH). Hydroxyl groups are especially important in biological chemistry because of their tendency to form hydrogen bonds both as donor and acceptor. This property is also related to their ability to increase hydrophilicity and water solubility. The hydroxyl group is especially predominant in the family of molecules known as carbohydrates.


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c) diol
 


A diol or glycol is a chemical compound containing two hydroxyl groups (-OH groups): -A geminal diol has two hydroxyl groups bonded to the same atom. -A vicinal diol is a diol with two hydroxyl groups in vicinal positions that is, attached to adjacent atoms.

Because diols are a common functional group arrangement, numerous methods of preparation have been developed: -Vicinal diols can be produced from the oxidation of alkenes, usually with dilute acidic potassium permanganate, also known as potassium manganate(VII). Using alkaline potassium manganate(VII) produces a color change from clear deep purple to clear green; acidic potassium manganate(VII) turns clear colorless. -Osmium tetroxide can similarly be used to oxidize alkenes to vicinal diols. -Hydrogen peroxide reacts with an alkene to the epoxide and then by saponification to the diol for example in the synthesis of trans-cyclohexanediol batch or by micro reactor:

-A chemical reaction called Sharpless asymmetric dihydroxylation can be used to produce chiral diols from alkenes using an osmate reagent and a chiral catalyst. -Another method is the Woodward cis-hydroxylation (cis diol) and the related Prévost reaction (anti diol), depicted below, which both use iodine and the silver salt of a carboxylic acid.

-In the Prins reaction ,3-diols an alkene and formaldehyde.

can

be

formed

in

a

reaction

between

-Geminal diols can be formed by the hydration of ketones.

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d) Experiments The purpose of this experiment is to develop:


-In early research, scientists have proposed this reaction:





+





In
higher
temperature


But at high temperatures the compound cannot be completed.

(

) decomposes and the reaction 


-My

teacher then asked to study this reaction (on different duration: 17h, 1 day, 2 days, 3 days, and 4 days):
 Low
T°






 +
Pyridine
+
DMAP


+





CH2Cl2


Compared to the previous reaction, pyridine does not react with the reagent at low temperature, so we add the DMAP to play the role of catalyst.

-Reaction mechanism (

=
R


)




+
 



 



 Pyridine
 
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ROH 


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e) Procedure 1) Initiate the reaction


-Put a test tube under vacuum and heat using a hair dryer for 5-10 min.
 -Leave for 10 min under hydrogen and kept under hydrogen.
 -Connect stirrer
 


-Weigh 21.6 mg of 





, and introduce it into the test tube.

-introducing DMAP, about a small spatula (0.61 mg).
 -add 1 ml of CH2Cl2 (solvent).
 -launch agitation
 -add 12,8 µl of BzOCl (protecting group)
 -add 9,3 µl of Pyridine 
 -stop hydrogen, and and allow for the number of days requested
 



 Hair dryer



 
 



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Product used during the reaction



 2) Stop the reaction


-Stop agitation
 -Take a column and put cotton in the narrow exit
 -Add powdered silicate to 1/8th of the column
 -Add hexane to form the resin, pressing with the blower to reach the limit that the silicate is not in contact with air, and then tap the column gently to compact the silicate
 -Place a flask beneath the column
 -Introduce little hexane in the test tube in cleaning entry
 -Add 5 spoonbill silicate
 -Add hexane to 1/3 of the column and mix
 -Pour the test tube in the column
 -Rinse 3 times with hexane and 2 times with ether
 -Rinse the column with ether 
 -Add ether to 1/3 of the column
 -Run the product in the flask until the silica is in contact with air
 -Clean entrance of the flask and exit of the column with ether
 -Finally, evaporating the solvent with the evaporator
 



 column with cotton

column with cotton and silicate

recovery of product and solvent



 


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 Evaporator


f) Chromatography After stopping the reaction, we use two methods of chromatography to purify the product. The first method used is the chromatography column and the second method is the TLC.
 


1) Column chromatography The substance to be purified is usually placed on the top of column and the solvent is run down the column. Fractions are collected and checked for compounds using TLC. The adsorbent for chromatography can be packed dry and solvents to be used for chromatography are used to equilibrate the adsorbent by flushing the column several times until equilibration is achieved. Alternatively, the column containing the adsorbent is packed wet/slurry method, and pressure is applied at the top of the column until the column is well packed. 2) TLC (Thin Layer Chromatography)

In TLC, the mobile phase, the solvent, creeps up the stationary phase (the adsorbent) by capillary action. The adsorbents are mixed with setting material by manufactures, which causes the film to set hard on drying. The adsorbent can be activated by heating at 100-110° for few hours. Other adsorbent adhere on glass plates without a setting agent. Thus some grades of adsorbents have prefixes, prefix G means that the adsorbent can cling to a glass plate and used it for TLC. Those lacking this binder have the letter H after any coding and are suitable for column chromatography. The materials to be purified or separated are spotted in a solvent close to the lower end of the plate and allowed to dry. The spots will need to be placed at such a distance so as to ensure that when the lower end of the plate is immersed in the solvent, the spot are a few mm above the eluting solvent. The plate is placed upright in a tank containing eluant. Elution is carried out in a closed tank to ensure equilibrium. Good separation can be achieved with square plate if a second elution is performed at right angles to the first using a second solvent system. Thin layer chromatography can be used to: -Monitor the progress of a reaction -Identify compounds present in a given substance -Determine the purity of a substance USTL‐IUT
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TLC (Thin Layer Chromatography)

3) Procedure - Prepare 400ml of solvent: 360ml of hexane and 45 ml of ether, and 20 test tubes.
 - Take a column and put cotton in the narrow exit
 - Fill half silicate, pour into a beaker with solvent, mix and pour into the column
 - Pressing with the blower to reach the limit that the silicate is not in contact with air, and then tap the column gently to compact the silicate
 - Add a little solvent and wait for a new faith limit
 - Place the test tube below the column
 - Introduce less than 1ml of ether in the flask of the product mix and pour into the column using a syringe. Rinse the ball twice with ether and poured into the column
 - Pour the solvent into the column and drain in the test tube, add the solvent promptly as to the silica does not come into contact with air
 - Wait until the first tube is filled to 3/4, rinse the column outlet with a little ether before going to the second tube
 - For the following fractions, fill the tubes to about half and rinse well with a little ether (to accelerate the process, you can use the blower putting pressure on the top of the column)
 - Once the 20 tube filled, identify in which fraction is the product, using TLC
 - Clean and weigh flask
 - Pour the tubes where is the product, and rinse with ether
 - Evaporate the solvent using an evaporator
 - place the flask under vacuum for 10 minutes
 - Weigh the flask and calculate the yield
 


Formation

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 Evaporator
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g) Results For this study, we have developed two results: the yield versus time of reaction and the purity of the product determines using mass chromatography.


1) The yields Duration

17h

1 day

2 days

3 days

4 days

Flask + product (g)


64,3554

64,9586

64,6431

64,4078

64,0949

Empty flask (g)

64,3434

64,9455

64,6277

64,3902

64,0750

Mass product (mg)

12

13,1

15,4

17,6

19,9

Reactant mass (mg)


21,6

21,6

21,3

21,6

21,5

Yield mass (%)


55,56

60,65

72,3

81,5

92,6

Yield molar mass (%)


37,5

41

48,8

55,5

62,5

M(




) = 216 g/mol

M(

) = 320 g/mol 


This result allows us to see that the reaction needs time to give a good performance.


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2) Mass chromatogram A mass chromatogram is a representation of mass spectrometry data as a chromatogram, where the x-axis represents time and the y-axis represents signal intensity. The source data contains mass information; however, it is not graphically represented in a mass chromatogram in favor of visualizing the time and signal intensity data. The most common use of this data representation is when mass spectrometry is used in conjunction with some form of chromatography such as in liquid chromatography-mass spectrometry or gas chromatography-mass spectrometry. In this case the time axis represents the retention time of the analyte identically to traditional chromatography using conventional detection means. The y-axis always represents "signal intensity", however, there are many different types of mass spectrometry experiments that this intensity may represent.
 


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