HIGHER SECONDARY TEACHERS SELECTION GRADE IN-SERVICE TRAINING 2012 Roll no.:- A-11 Name: - Dr. Sanjay Narhar Karmarkar College:- Vidya Bhavan high School and Jr. College Model Colony, Shivajinagar, Pune-411016 Mobile no.: +919822341195 Action Research Higher Secondary teachers Selection Grade: In-service training program 1June to 5June 2012 ALPHABETICAL ORDER OF NAME REACTIONS AND ITS UTILITY IN CONVERSIONS AND REAGENTS IN ORGANIC CHEMISTRY (SECTION II) Training Center: - S.P. College, Pune-411004
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Solution remains clear Reducing sugar is not present
Biuret test:Procedure
An aqueous sample is treated with an equal volume of 1% strong base (sodium or potassium
hydroxide most often) followed by a few drops of aqueous copper(II) sulfate. If the solution
turns purple, protein is present. 5–160 mg/mL can be determined.
The Biuret reagent is made of potassium hydroxide (KOH) and hydrated copper(II) sulfate,
together with potassium sodium tartrate.[2] The reagent turns from blue to violet in the presence
of proteins, blue to pink when combined with short-chain polypeptides.
Brown Hydroboration
The syn-addition of hydroboranes to alkenes occurs with predictable selectivity, wherein the boron adds preferentially to the least hindered carbon. This selectivity is enhanced if sterically demanding boranes are used.
Coupling the hydroboration with a subsequent oxidation of the new formed borane yields anti - Markovnikov alcohols. The hydroboration/oxidation sequence constitutes a powerful method for the regio- and stereoselective synthesis of alcohols.
The product boranes may also be used as starting materials for other reactions, such as Suzuki Couplings (see Recent Literature).
Mechanism of the Brown Hydroboration
The selectivity of the first addition of borane can be relatively low:
Cannizzaro reaction: named after its discoverer Stanislao Cannizzaro, is a chemical reaction
that involves the base-induced disproportionation of an aldehyde.[1][2] Cannizzaro first
accomplished this transformation in 1853, when he obtained benzyl alcohol and potassium
benzoate from the treatment of benzaldehyde with potash (potassium carbonate). More
typically, the reaction would be conducted with sodium or potassium hydroxide:
2 C6H5CHO + KOH → C6H5CH2OH + C6H5CO2K
The oxidation product is a salt of a carboxylic acid and the reduction product is an alcohol.[3] For
aldehydes with a hydrogen atom alpha to the carbonyl, i.e. R2CHCHO, the preferred reaction is
an aldol condensation, originating from deprotonation of this hydrogen. This reaction restricts
An interesting variant, the Crossed Cannizzaro Reaction, uses formaldehyde as reducing agent:
At the present time, various oxidizing and reducing agents can be used to carry out such conversions (with higher yields), so that today the Cannizzaro Reaction has limited synthetic utility except for the abovementioned conversion of α-keto aldehydes.
The Cannizzaro Reaction should be kept in mind as a source of potential side products when aldehydes are treated under basic conditions.
HOME WORK:A)Write with equation following conversion?
1)Formaldehyde to Methonol
2)Formaldehyde to Sodium Formate
B)Write short note on Mixed aldol condensation
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Claisen condensation:
The Claisen condensation (not to be confused with the Claisen rearrangement) is a carbon–
carbon bond forming reaction that occurs between two esters or one ester and another carbonyl
compound in the presence of a strong base, resulting in a β-keto ester or a β-diketone [1] . It is
named after Rainer Ludwig Claisen, who first published his work on the reaction in
Clemmensen reduction: is a chemical reaction described as a reduction of ketones (or
aldehydes) to alkanes using zinc amalgam and hydrochloric acid.[1][2][3] This reaction is named
after Erik Christian Clemmensen, a Danish chemist.[4
he Clemmensen reduction is particularly effective at reducing aryl-alkyl ketones.[5][6] With
aliphatic or cyclic ketones, zinc metal reduction is much more effective.[7]
HOME WORK:Write with equation following conversion?
The Lewis or Brønstedt acid-catalyzed esterification of carboxylic acids with alcohols to give esters is a typical reaction in which the products and reactants are in equilibrium.
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The equilibrium may be influenced by either removing one product from the reaction mixture (for example, removal of the water by azeotropic distillation or absorption by molecular sieves) or by employing an excess of one reactant.
Mechanism of the Fischer Esterification
Addition of a proton (e.g.: p-TsOH, H2SO4) or a Lewis acid leads to a more reactive electrophile. Nucleophilic attack of the alcohol gives a tetrahedral intermediate in which there are two equivalent hydroxyl groups. One of these hydroxyl groups is eliminated after a proton shift (tautomerism) to give water and the ester.
Alternative reactions employ coupling reagents such as DCC (Steglich Esterification), preformed esters (transesterification), carboxylic acid chlorides or anhydrides (see overview). These reactions avoid the production of water. Another pathway for the production of esters is the formation of a carboxylate anion, which then reacts as a nucleophile with an electrophile (similar reactions can be found here). Esters may also be produced by oxidations, namely by the Baeyer-Villiger oxidation and oxidative esterifications.
Fischer indole synthesis:is a chemical reaction that produces the aromatic heterocycle indole
from a (substituted) phenylhydrazine and an aldehyde or ketone under acidic conditions.[1][2]
The reaction was discovered in 1883 by Hermann Emil Fischer. Today antimigraine drugs of
the triptan class are often synthesized by this method.
Lindlar catalyst: is a heterogeneous catalyst that consists of palladium deposited on calcium
carbonate and treated with various forms of lead. The lead additive serves to deactivate the
palladium sites. A variety of "catalyst poisons" have been used including lead acetate and lead
oxide. The palladium content of the catalyst is usually 5% by weight. The catalyst is used for the
hydrogenation of alkynes to alkenes (i.e. without further reduction into alkanes).
Markovnikov's Rule
Markovnikov Rule predicts the regiochemistry of HX addition to unsymmetrically substituted alkenes.
The halide component of HX bonds preferentially at the more highly substituted carbon, whereas the hydrogen prefers the carbon which already contains more hydrogens.
Anti-Markovnikov
Some reactions do not follow Markovnikov's Rule, and anti-Markovnikov products are isolated. This is a feature for example of radical induced additions of HX and of Hydroboration.
Mechanism
The proton adds first to the carbon-carbon double bond. The carbon bearing more substituents forms a more stable carbenium ion; attack of bromide ion follows in a second step:
Markovnikov:Radical reactions require an initiation step. In this example, a bromo radical is formed.
The reversal of the regiochemistry of addition is the result of the reversal of the order in which the two components add to the alkene. Radical addition leads to the formation of the more stable radical, which reacts with HBr to give product and a new bromo radical:
Anti-Markovnikov
Nef reaction: is an organic reaction describing the acid hydrolysis of a salt of a primary or
secondary nitroalkane (1) to an aldehyde or a ketone (3) and nitrous oxide (4).[1][2][3]
List of organic reagents and important chemical reaction with suitable example.
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CHAPTER III6Literature Use:-
The Main source of this project was the web!
References used were :
www.google.com/chemistry
www.wikipedia.org
www.chem.queens.ca
www.arizona.edu
Document is prepared in Times New Roman format (font size)
7Methodology Used:
Data is extracted from the internet. Data is information base on the facts from the syllabus of
std XII. from the name reaction and preparation of various organic compounds student should
study conversions some illustrative examples with chart is enclosed .after reading this chart
later on test was conducted in different groups to test the knowledge of student. A questionnaire
was distributed amongst the students and also they were asked to write small test regarding their
syllabi.
Class XII: Chemistry
Important Reactions used for Organic Chemistry ConversionsIn XII board exam, word problems (conversions) covering “Properties andReactions of Functional Groups” usually carry a weightage of 5 marks. So, itis important that you do not miss out on these particular types of questionswhile preparing for your exams.Students tend to get confused while solving questions based on organicconversions. Given below are a few conversions, explained in small logicalchunks which are easy to remember.Broadly you can classify conversions into two types – aliphatic and aromatic.1. Aliphatic Conversionsa. For stepping up the series:Stepping up the series means that the product has one carbon more thanthat of reactant. For such kind of a conversion, convert the given compoundto an alkyl halide and then to a cyanide and then to the required organiccompound as asked in the question. This way, the product has one carbonmore than the reactant.
b. For stepping down the series:Stepping down the series means that the product has one carbon less thanthat of its reactant. For such kind of a conversion, convert the givencompound to an amide and then let it undergo Hoffmann bromamidedegradation reaction. Then you convert it to the required product as asked inthe question.
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c. Reaction with Grignard’s reagent:Grignard’s reagent is a versatile reagent and can be used for many conversions.
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There are two types of conversions possible in this case:a. When the functional group contains carbon atom:
b. When the functional group does not contain carbon atom:
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The following chart will help student to understand preparation reactions quiz of organic compounds ,as illustrative example one reference site is given to the students , then they can memories varieties of equation by this method .
Similarly verity of list of reagents and its utility can be demonstrated an one can find these reaction easier to remember some illustrative examples are given below