GATE Chemistry (CY) Updated Syllabus

GATE Chemistry (CY) Updated Syllabus

By   08:22   3 comments:

GATE is an all india examination administered and conducted jointly by the Indian Institute of Science (IISc) and IITs on behalf of National Coordination Board GATE, Department of Higher Education, Ministry of Human Resource Development (MHRD)

GATE Syllabus for Chemistry (CY) 

Updated Syllabus for upcoming GATE exam is as follows

Section 1: Physical Chemistry

Structure: Postulates of quantum mechanics. Time dependent and time independent Schrödinger equations. Born interpretation. Particle in a box. Harmonic oscillator. Rigid rotor. Hydrogen atom: atomic orbitals. Multi-electron atoms: orbital approximation. Variation and first order perturbation techniques. Chemical bonding: Valence bond theory and LCAO-MO theory. Hybrid orbitals. Applications of LCAO-MOT to H2+, H2 and other homonuclear diatomic molecules, heteronuclear diatomic molecules like HF, CO, NO, and to simple delocalized π– electron systems. Hückel approximation and its application to annular π – electron systems. Symmetry elements and operations. Point groups and character tables. Origin of selection rules for rotational, vibrational, electronic and Raman spectroscopy of diatomic and polyatomic molecules. Einstein coefficients. Relationship of transition moment integral with molar extinction coefficient and oscillator strength. Basic principles of nuclear magnetic resonance: nuclear g factor, chemical shift, nuclear coupling.

Equilibrium: Laws of thermodynamics. Standard states. Thermochemistry. Thermodynamic functions and their relationships: Gibbs-Helmholtz and Maxwell relations, van’t Hoff equation. Criteria of spontaneity and equilibrium. Absolute entropy. Partial molar quantities. Thermodynamics of mixing. Chemical potential. Fugacity, activity and activity coefficients. Chemical equilibria. Dependence of equilibrium constant on temperature and pressure. Non-ideal solutions. Ionic mobility and conductivity. Debye-Hückel limiting law. Debye-Hückel-Onsager equation. Standard electrode potentials and electrochemical cells. Potentiometric and conductometric titrations. Phase rule. Clausius-Clapeyron equation. Phase diagram of one component systems: CO2, H2O, S; two component systems: liquid-vapour, liquid-liquid and solid-liquid systems. Fractional distillation. Azeotropes and eutectics. Statistical thermodynamics: microcanonical and canonical ensembles, Boltzmann distribution, partition functions and thermodynamic properties.

Kinetics: Transition state theory: Eyring equation, thermodynamic aspects. Potential energy surfaces and classical trajectories. Elementary, parallel, opposing and consecutive reactions. Steady state approximation. Mechanisms of complex reactions. Unimolecular reactions. Kinetics of polymerization and enzyme catalysis. Fast reaction kinetics: relaxation and flow methods. Kinetics of photochemical and photophysical processes.

Surfaces and Interfaces: Physisorption and chemisorption. Langmuir, Freundlich and BET isotherms. Surface catalysis: Langmuir-Hinshelwood mechanism. Surface tension, viscosity. Self-assembly. Physical chemistry of colloids, micelles and macromolecules.

Section 2: Inorganic Chemistry

Main Group Elements: Hydrides, halides, oxides, oxoacids, nitrides, sulfides – shapes and reactivity. Structure and bonding of boranes, carboranes, silicones, silicates, boron nitride, borazines and phosphazenes. Allotropes of carbon. Chemistry of noble gases, pseudohalogens, and interhalogen compounds. Acid-base concepts.

Transition Elements: Coordination chemistry – structure and isomerism, theories of bonding (VBT, CFT, and MOT). Energy level diagrams in various crystal fields, CFSE, applications of CFT, Jahn-Teller distortion. Electronic spectra of transition metal complexes: spectroscopic term symbols, selection rules, Orgel diagrams, charge-transfer spectra. Magnetic
properties of transition metal complexes. Reaction mechanisms: kinetic and thermodynamic stability, substitution and redox reactions.

Lanthanides and Actinides: Recovery. Periodic properties, spectra and magnetic properties.

Organometallics: 18-Electron rule; metal-alkyl, metal-carbonyl, metal-olefin and metal-carbene complexes and metallocenes. Fluxionality in organometallic complexes. Types of organometallic reactions. Homogeneous catalysis - Hydrogenation, hydroformylation, acetic acid synthesis, metathesis and olefin oxidation. Heterogeneous catalysis - Fischer-Tropsch reaction, Ziegler-Natta polymerization.

Radioactivity: Decay processes, half-life of radioactive elements, fission and fusion processes.

Bioinorganic Chemistry: Ion (Na+ and K+) transport, oxygen binding, transport and utilization, electron transfer reactions, nitrogen fixation, metalloenzymes containing magnesium, molybdenum, iron, cobalt, copper and zinc.

Solids: Crystal systems and lattices, Miller planes, crystal packing, crystal defects, Bragg’s law, ionic crystals, structures of AX, AX2, ABX3 type compounds, spinels, band theory, metals and semiconductors.
Instrumental Methods of Analysis: UV-visible spectrophotometry, NMR and ESR spectroscopy, mass spectrometry. Chromatography including GC and HPLC. Electroanalytical methods- polarography, cyclic voltammetry, ion-selective electrodes. Thermoanalytical methods.

Section 3: Organic Chemistry

Stereochemistry: Chirality of organic molecules with or without chiral centres and determination of their absolute configurations. Relative stereochemistry in compounds having more than one stereogenic centre. Homotopic, enantiotopic and diastereotopic atoms, groups and faces. Stereoselective and stereospecific synthesis. Conformational analysis of acyclic and cyclic compounds. Geometrical isomerism. Configurational and conformational effects, and neighbouring group participation on reactivity and selectivity/specificity.

Reaction Mechanisms: Basic mechanistic concepts – kinetic versus thermodynamic control, Hammond’s postulate and Curtin-Hammett principle. Methods of determining reaction mechanisms through identification of products, intermediates and isotopic labeling. Nucleophilic and electrophilic substitution reactions (both aromatic and aliphatic). Addition reactions to carbon-carbon and carbon-heteroatom (N,O) multiple bonds. Elimination reactions. Reactive intermediates – carbocations, carbanions, carbenes, nitrenes, arynes and free radicals. Molecular rearrangements involving electron deficient atoms.
 

Organic Synthesis: Synthesis, reactions, mechanisms and selectivity involving the following classes of compounds – alkenes, alkynes, arenes, alcohols, phenols, aldehydes, ketones, carboxylic acids, esters, nitriles, halides, nitro compounds, amines and amides. Uses of Mg, Li, Cu, B, Zn and Si based reagents in organic synthesis. Carbon-carbon bond formation through coupling reactions - Heck, Suzuki, Stille and Sonogoshira. Concepts of multistep
synthesis - retrosynthetic analysis, strategic disconnections, synthons and synthetic equivalents. Umpolung reactivity – formyl and acyl anion equivalents. Selectivity in organic synthesis – chemo-, regio- and stereoselectivity. Protection and deprotection of functional groups. Concepts of asymmetric synthesis – resolution (including enzymatic), desymmetrization and use of chiral auxilliaries. Carbon-carbon bond forming reactions through enolates (including boron enolates), enamines and silyl enol ethers. Michael addition reaction. Stereoselective addition to C=O groups (Cram and Felkin-Anh models).

Pericyclic Reactions and Photochemistry: Electrocyclic, cycloaddition and sigmatropic reactions. Orbital correlations - FMO and PMO treatments. Photochemistry of alkenes, arenes and carbonyl compounds. Photooxidation and photoreduction. Di-π-methane rearrangement, Barton reaction.

Heterocyclic Compounds: Structure, preparation, properties and reactions of furan, pyrrole, thiophene, pyridine, indole, quinoline and isoquinoline.

Biomolecules: Structure, properties and reactions of mono- and di-saccharides, physicochemical properties of amino acids, chemical synthesis of peptides, structural features of proteins, nucleic acids, steroids, terpenoids, carotenoids, and alkaloids.

Spectroscopy: Applications of UV-visible, IR, NMR and Mass spectrometry in the structural determination of organic molecules.

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GATE Chemistry (CY) Previous Year Question Papers

GATE Chemistry (CY) Previous Year Question Papers

By   04:00   3 comments:

From this post you can download previous year papers in PDF format,
Below is the GATE Chemistry Previous Year Question Papers for last 10 years from 2007-2016. GATE Chemistry aspirants can download.
You can download each file by clicking against repective year.
Answer Key are also provided for some of the papers.

Get Updated Syllabus for GATE  Chemistry (CY) Click Here

GATE Chemistry (CY) Question Paper 2016  Click Here to download in PDF format 


GATE Chemistry (CY) Question Paper 2015  Click Here to download in PDF format


GATE Chemistry (CY) Question Paper 2014 Click Here to download in PDF format 
GATE Chemistry (CY) Answer Key 2014


GATE Chemistry (CY) Question Paper 2013  Click Here to download in PDF format 
GATE Chemistry (CY) Answer Key 2013


GATE Chemistry (CY) Question Paper 2012   Click Here to download in PDF format 


GATE Chemistry (CY) Question Paper 2011  Click Here to download in PDF format 


GATE Chemistry (CY) Question Paper 2010 Click Here to download in PDF format 


GATE Chemistry (CY) Question Paper 2009  Click Here to download in PDF format 


GATE Chemistry (CY) Question Paper 2008  Click Here to download in PDF format 


GATE Chemistry (CY) Question Paper 2007  Click Here to download in PDF format

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CSIR NET JRF DEC 2016 Section A (Solved with Explanation)

CSIR NET JRF DEC 2016 Section A (Solved with Explanation)

By   00:40   7 comments:

Yet another examination of CSIR NET JRF has ended, I hope you all must've performed well. Now most of us want to check our answers and are wondering to check how much marks are we getting. From last morning itself whole social media groups and pages are filled with screenshots of questions expecting solutions. 

 In this post I'm trying to post solved explanation of some problems from CSIR DEC 2016 examination. Many of my fellow chemists were asking for detailed soluttion of questions of Section A of CSIR NET exam held on  18th Dec 2016. I've solved some of the problems and Images of solution are below. All questions are solved by me with best of my knowledge, feel free to do any query.

Note: Answers are solved as per best of my knowledge, I can not ensure it's correctness according to CSIR, The answers may vary with Final AnswerKey.

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Carbon-13 NMR

Carbon-13 NMR

By   23:08   No comments:

In this post we will discuss about ¹³C NMR. This topic is well covered under Spectroscopy. It is one of the most important topic as per CSIR syllabus. Under this post we will discuss some basics of ¹³C NMR and at the end of the post there are some Problems related to the topic asked previously in CSIR Examinations.

What is ¹³C NMR?

Nuclear Magnetic Resonance (NMR) spectroscopy has become the dominant method of analysis for organic compounds, because in many cases it provides a way to determine an entire structure using one set of analytical tests. It is also increasingly used in inorganic chemistry and biochemistry, where it also provides a lot of valuable structural information.

Nuclear Magnetic Resonance (NMR) Spectroscopy is not limited to the study of protons. Any element with a nuclear spin (¹³C, ¹⁷O, ¹⁹F, ³¹P and many others) will give rise to an NMR signal.Carbon-13 NMR (¹³C NMR or referred to as carbon NMR) is the application of nuclear magnetic resonance (NMR) spectroscopy applicable to carbon. It is similar to proton NMR (1 H NMR) and allows the identification of carbon atoms whereas in other identification of H. As such ¹³C NMR is an important tool in chemical structure elucidation in organic chemistry. ¹³C NMR detects only the 13C isotope of carbon, whose natural abundance is only 1.1%, because  the main carbon isotope, 12 C, is not detectable by NMR since it has zero net spin.



Some of the properties of ¹³C NMR:

• ¹³C has only about 1.1% natural abundance (of carbon atoms)
• ¹²C does not exhibit NMR behaviour (I=0)
•  ¹³C nucleus is also a spin 1/2 nucleus
• ¹³C nucleus is about 400 times less sensitive than H nucleus to the NMR phenomena
• Due to the low abundance, we do not usually see ¹³C-¹³C coupling
• Chemical shift range is normally 0 to 220 ppm
• Chemical shifts are also measured with respect to tetramethylsilane, (CH₃)₄Si (i.e. TMS)
• Similar factors affect the chemical shifts in ¹³C as seen for H-NMR
• Long relaxation times (excited state to ground state) mean no integrations
• "Normal" ¹³C spectra are "broadband, proton decoupled" so the peaks show as single lines
• Number of peaks indicates the number of types of C

Additional Detailed Notes on this topic is provided below:

Note: these notes belong to MIT University and These are posted here just for a detailed overview of the topic.


MUST VIEW:
Practice Problems on Spectroscopy
Isolobal Analogy
18 el

This is sample image of Notes, Full notes can be downloaded from below link

Download Notes on ¹³C NMR Spectrascopy  Click Here

Practice Problems on ¹³C NMR Spectroscopy

 Ques.1: Predict the number of ¹³C NMR signals in the following compounds:

1. Benzene
2. naphthalene
3. Anthracene
4. pentacene
5. cyclohexane
6. salicylic acid
7. beta napthol
8. camphor
9. alpha napthol
10. di benza anthracene
11. 7-norborane
12. resorcinol
13. 2-pentanone
14. pinene
15. menthol
16. aspirin
17. alpha-terpenol
18. citral
19. vanilin
20. toulene
21. 4-chloro benzonitrile

 Questions Asked In CSIR NET JRF, GATE and other Examinations:

[CSIR JUNE 2012]
The number of signals that appear in broad band decoupled ¹³C NMR spectrum of  phenanthracene and anthracene is:  

 

[CSIR JUNE 2012]

 [CSIR DEC 2014]

  [CSIR JUNE 2014]

 [CSIR JUNE 2013]

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Practice Problems on Organometallic Chemistry

Practice Problems on Organometallic Chemistry

By   10:26   No comments:

This post contains Practice Problems on Organometallic Chemistry, These papers are prepared by Jadveer Singh Sir of Chemistry Classes Allahabad. Under His Excellent Guidance many students have Qualified for CSIR and IIT JAM. Standard of Questions are maintained as per CSIR Level.

This set of questions for all aspirants of CSIR NET JRF, GATE, TIFR and IIT JAM, keep solving it and post your answers on our Facebook page, your Involvement will help you and others clearing concepts and solving answers quickly,
your answers will be appreciated. [dont forget to mention answer number with section]
Or
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2. Practice Problems on Solid State

•  A sample Image has been added here , you can download full practice paper from link given below.

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• Practice Problem on Organometallic Chemistry Part I............ Click Here
• Practice Problem on Organometallic Chemistry Part II........... Click Here
• Practice Problem on Organometallic Chemistry Part III.......... Click Here

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Boranes- Assigning Closo, Nido, Arachno, Hypo Nomenclature

Boranes- Assigning Closo, Nido, Arachno, Hypo Nomenclature

By   06:19   8 comments:

In this post we will learn how to assign Nomenclature (closo, nido, arachno, hypo)  to a given Borane and Also We'll Learn How to Calculate number of B-H-B bonds, B-B-B bonds in a given Borane through STYX code . According to Some pf the previous papers of CSIR, JAM and other Competitive Examinations, Questions related to this topic is frequently asked. I hope it'll help you and you'll be able to solve these questions easily after reading this post. 

Source: google.com

Structures and Bonding:

There are three important structures of boranes (closo-, nido- and arachno-) .In this structures the boron atoms are occuping the corners of a polyhedron in which the boron atoms can be bound together or not. These structures are so called cage structures.  

a) closo – B_nH_n^2-    b) nido – B_nH_n+4   c) arachno – B_nH_n+6  

Examples:

a)      B₆H₆^2- is closo-type and the 6 B’s lie on the corners of a octahedron

b)      B₅H₉ is nido-type and the 5 B’s lie on the corners of a square pyramid where one corner is removed

c)      B₄H₁₀ is arachno-type and the 4 B’s lie on the corners of an octaherdron where two corners are removed

Boranes have an electron-deficient, but they are coordinated by four atoms. This is the reason why they are forming unusual bonds, because there are not enough electrons to form the bonds. The dicription of the bonding in higher boranes was formulated by William Lipscomb and is as follows:

3-center 2-electron B-H-B hydrogen bridges and 3-center 2-electron B-B-B bonds

Must Read: 18 Electron rule 

Wade Rules

A second method to determine the geometry of boranes are the Wade rules. The Wade rules are a correlation between the number of electrons , the formula and the shape of the molecule. To use this method, the total number of valence electrons that are forming the bonds must be determined (n = Number of boron atoms).

Kenneth Wade (1932-2014) was a faculty at Durham University UK. In the early 1970’s he formulated the Wades rules which provided a major breakthrough in the qualitative understanding of the electron deficient multicentre bonding of boron hydrides and their shape based classification.
 

According to Wade his rule correlates skeletal structures of boranes, carboranes,  hetero boranes and their anions (closo, nido, arachno, hypho) with the number of skeletal electron pairs they contain.
The rule states that clusters having n skeletal atoms (vertices) will adopt closo  structures if it is held together by n+1 skeletal bonding electron pairs; nido if held  together by n+2 skeletal electron pairs, arachno if held together by n+3 skeletal. electron pairs, hypho if held together by n+4 skeletal electron pairs and klado if held together by n+5 skeletal electron pairs.
For applying this rule one need to determine the number of skeletal electron pairs in a  cluster. Each BH unit furnishes 2 skeletal bonding electrons, each B as such gives three skeletal electrons, each C-H unit of a carborane furnishes 3 skeletal bonding electrons and each additional H· furnishes 1 skeletal bonding electron. Ionic charges must be included in the electron count. 

Extending this to borane clusters with other hetero-elements, one may replace  C, Si, Ge and Sn of a cluster with a BH unit; N, P and As with a BH2 unit and S and Se with a BH3 unit for counting purpose.
 

 Some Examples on Wade Rule:

Lipscomb's STYX codes:

The styx number was introduced to aid in electron counting where 

s = count of 3-center B-H-B bonds;
t = count of 3-center B-B-B bonds; 

y = count of 2-center B-B bonds and 

x = count of BH2 groups. 

Lipscomb's methodology has largely been superseded by a molecular orbital approach, although it still affords insights. The results of this have been summarized in a simple but powerful rule, PSEPT (Polyhedral Skeletal Electron Pair Theory), often known as Wade's rules, that can be used to predict the cluster type, closo-, nido-, etc. The power of this rule is its ease of use and general applicability to many different cluster types other than boranes."

 Here is a method to Calculate STYX code for different boranes.

 NOTE: For Compounds having B6 or more and Compounds with B-H difference of 4 is directly taken as S values,
for example. In case of B6H10 diff is 4 so S =4 we will not take 2, _, _, 2. But we will take 4, _, _,0 as S and X values

• You can also calculate STYX code directly just by entering the type of boron you want to calculate for by going through this link: STYX Calculator

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Practice Problems on Solid State

Practice Problems on Solid State

By   03:40   4 comments:

This post contains Some Practice Problems on Solid State,. Standard of Questions are maintained as per CSIR Level.

This set of questions for all aspirants of CSIR NET JRF, GATE, TIFR and IIT JAM, keep solving it and post ur answers on our Facebook page, your Involvement will help you and others clearing concepts and solving answers quickly,
your answers will be appreciated. [dont forget to mention answer number with section]
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Supplementary Notes On Stereochemistry

Supplementary Notes On Stereochemistry

By   11:08   3 comments:

This Post is related to Concepts in Stereochemistry and it's application.
Some of the key points of this notes is:

• Relationship between Symmetry and Chirality.
• Some terminology used in Stereochemistry (enantiomers, diastereomers, optical activity, etc)
• R/S Nomenclature System.
• Assigning absolute structures in various projections of chiral molecules.
• molecules with more than one Chiral Centres.

NOTE: This Notes is just for quick revision, for detailed study i would suggest you to Go Through books.

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Conformational Analysis Of Organic Reactions

Conformational Analysis Of Organic Reactions

By   12:09   No comments:

This post contains Conformational Analysis of Organic Reactions and Their effect on Kinetic and Thermodynamic Stability of product.

Stereochemistry and Conformation of Products in Organic Reaction is very much important, Stereo of a compound determines its functions.

Some Of the topics Covered under this post are:

• Conformational Analysis of Different Organic Compounds

• Kinetics and Thermodynamics of Organic Reactions.

• Reaction Mechanism and Conformational Effect on Reactivity.

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1. Organic reagents used in Oxidation Reactions
2. Organic Reagents used in Reduction Reactions.

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Organic Reagents For Reduction Reaction (Reduction Reactions)

Organic Reagents For Reduction Reaction (Reduction Reactions)

By   10:44   No comments:

Extending Our previous post on Organic Reagents for Oxidation Reaction, This Post contains Organic Reagents for Reduction Reactions.
Reduction of an organic compound usually include conversion of functional groups like carboxylic acid to aldehyde, ketones and aldehyde to primary and secondory alcohol respectively, Nitro groups to Amino group, etc. These reagents are very useful for these conversions. The resulting product will have a definite stereochemistry and to know this it becomes very essential to learn mechanisms of these conversions too.

These Notes include all reagents alongwith proper explanation, examples and mechanism.

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Reagents For Oxidation Reaction (Oxidising Reagents)

Reagents For Oxidation Reaction (Oxidising Reagents)

By   11:55   No comments:

This Post contains Organic Reagents for Oxidation Reactions.
The Notes are from NPTEL [The National Programme on Technology Enhanced Learning (NPTEL), a project funded by the Ministry of Human Resource Development (MHRD)] 

These Notes include all reagents alongwith proper explanation and mechanism.
Download and enjoy

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Practice Problems On Coordination Chemistry

Practice Problems On Coordination Chemistry

By   12:39   No comments:

Presenting Some Practice Problems on Coordination Chemistry, These papers are prepared by Jadveer Singh Sir of Chemistry Classes Allahabad. Under His Excellent Guidance many students have Qualified for CSIR and IIT JAM. Standard of Questions are maintained as per CSIR Level.

It's a set of questions for all aspirants of CSIR NET JRF, GATE, TIFR and IIT JAM, keep solving it and post ur answers on our Facebook page, your Involvement will help you and others clearing concepts and solving answers quickly,
your answers will be appreciated. [dont forget to mention answer number with section]
Or
You can send me your answers via email from here

Answers will be posted on our Facebook Page on Sunday 11th Sept.

For Solving these Problems you can Take Help from some of these Standard Books:
James E Huhyee.
Shivers and Atkins,
Missler and Tarr ,

You can find these Books on This Website Under Books Label.

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Cabenes - A Brief Introduction

Cabenes - A Brief Introduction

By   14:40   No comments:

A carbene is a neutral molecule which contains a carbon atom with an electron valency of 6 (two bonds and two nonbonding electrons). They are a very reactive type of compound, often too reactive to be observed.

Carbenes can be classified into two major forms:

1. Singlet Carbene
2. Triplet Carbene

 The two classes of carbenes are singlet and triplet carbenes. Singlet carbenes are spin-paired. In the language of valence bond theory, the molecule adopts an sp² hybrid structure. Triplet carbenes have two unpaired electrons.

Properties Of Singlet Carbenes

•  spin multiplicity (2s+1) = 1

• diamagnetic in nature.

• Both Non-Bonding electrons are paired.

• sp² hybridised   

• less stable

Properties of Triplet Carbene 

•  spin multiplicity (2s+1) =3

• paramagnetic in nature.

• Both Non-Bonding electrons are unpaired.

• sp² hybridised   

• more stable

 

Why is Triplet Carbene more stable than Singlet Carbene?

Fairly well asked question, One of the most basic explanation to this question is, In singlet carbene, there are two electrons which are in the same orbital and they repell each one another since they have both the same negative electric charge. in a triplet carbene the two electrons are in different orbitals and there is no repusive force between them

 

Methods Of Formation Of carbenes:

 1. From Haloform

[NOTE:as the Leaving Group ability of the leaving group increases, the rate of formation of carbene increases]

2. From Ketene

3. From Diazo Compounds

 

 4. From Acid Halide

5. From Tosylhydrazones

 6. From Active methylene Compounds

 7. Shapiro Reaction

In this Reaction, the tosyl hydrazones (p-Toluenesulfonyl hydrazones) of aliphatic aldehydes or ketones furnish more substituted alkenes when treated with strong bases like NaOMe, NaH, LiH, NaNH₂ etc.

mechanism:

In aprotic solvents, the diazo compound loses dinitrogen and gives a carbene, which undergoes a faster 1,2-hydrogen shift to furnish a Z-alkene predominantly. 

Chemical Properties of Carbenes

In this section we are going to discuss some Common Name Reactions in which Carbenes are obtained as reaction intermediate.

Wolf Rearrangement

Insertion Reactions of Carbene

1. Insertion with Alkene:

i)insertion of singlet carbene:

ii) insertion of triplet carbene:

2. Insertion with Benzene:

3. Insertion with Pyrrol (Riemann Tiemann Reaction)

Simon Smith Carbene

Arndt Ester Synthesis:

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