MASS SPECTROSCOPY ( Molecular ion, Base peak, Isotopic abundance, Metastable ...Sachin Kale
CONTENT:
Molecular Ion Peak
Significance of Molecular ion & Graphically Method
Base Peak
Isotopic Abundance
Metastable Ion
Significance of Metastable ion
Nitrogen Rule & graphs
Formulation of Rule
MASS SPECTROSCOPY ( Molecular ion, Base peak, Isotopic abundance, Metastable ...Sachin Kale
CONTENT:
Molecular Ion Peak
Significance of Molecular ion & Graphically Method
Base Peak
Isotopic Abundance
Metastable Ion
Significance of Metastable ion
Nitrogen Rule & graphs
Formulation of Rule
NMR- Diamagnetic Anisotropy and its effect on chemical shiftD.R. Chandravanshi
The shift in the position of the NMR region resulting from the shielding and deshielding by electrons is called chemical shift.
When a proton is present inside the magnetic field more close to an electro positive atom more applied magnetic field is required to cause excitation. This effect is called shielding effect.
When a proton is present outside the magnetic field close to a electronegative atom less applied magnetic field is required to cause excitation . This effect is called deshielding effect
IR SPECTROSCOPY, INTRODUCTION, PRINCIPLE, THEORY, FATE OF ABSORBED RADIATION, FERMI RESONANCE, FINGERPRINT REGION, VIBRATIONS, FACTORS AFFECTING ABSORPTION OF IR RADIATION, SAMPLING TECHNIQUES, APPLICATIONS OF IR SPECTROSCOPY.
In molecular spectroscopy, a Jablonski diagram is a diagram that illustrates the electronic states of a molecule and the transitions between them. The states are arranged vertically by energy and grouped horizontally by spin multiplicity.
When there are two functional groups of unequal reactivity within a molecule, the more reactive group can be made to react alone, but it may not be possible to react the less reactive functional group selectively.
A group the use of which makes possible to react a less reactive functional group selectively in presence of a more reactive group is known as protecting group.
A protecting group blocks the reactivity of a functional group by converting it into a different group which is inert to the conditions of some reaction(s) that is to be carried out as part of a synthetic route
NMR- Diamagnetic Anisotropy and its effect on chemical shiftD.R. Chandravanshi
The shift in the position of the NMR region resulting from the shielding and deshielding by electrons is called chemical shift.
When a proton is present inside the magnetic field more close to an electro positive atom more applied magnetic field is required to cause excitation. This effect is called shielding effect.
When a proton is present outside the magnetic field close to a electronegative atom less applied magnetic field is required to cause excitation . This effect is called deshielding effect
IR SPECTROSCOPY, INTRODUCTION, PRINCIPLE, THEORY, FATE OF ABSORBED RADIATION, FERMI RESONANCE, FINGERPRINT REGION, VIBRATIONS, FACTORS AFFECTING ABSORPTION OF IR RADIATION, SAMPLING TECHNIQUES, APPLICATIONS OF IR SPECTROSCOPY.
In molecular spectroscopy, a Jablonski diagram is a diagram that illustrates the electronic states of a molecule and the transitions between them. The states are arranged vertically by energy and grouped horizontally by spin multiplicity.
When there are two functional groups of unequal reactivity within a molecule, the more reactive group can be made to react alone, but it may not be possible to react the less reactive functional group selectively.
A group the use of which makes possible to react a less reactive functional group selectively in presence of a more reactive group is known as protecting group.
A protecting group blocks the reactivity of a functional group by converting it into a different group which is inert to the conditions of some reaction(s) that is to be carried out as part of a synthetic route
Ultraviolet–visible spectroscopy or ultraviolet-visible spectrophotometry (UV-Vis or UV/Vis) refers to absorption spectroscopy or reflectance spectroscopy in the ultraviolet-visible spectral region. This means it uses light in the visible and adjacent ranges.
INTRODUCTION TO UV-VISIBLE SPECTROSCOPYJunaid Khan
UV-visible spectroscopy is the classical and the most reliable technique for qualitative and quantitative analysis of organic compounds. It involves detection of light absorbed by the sample and correlates it with concentration of the solute.
UV spectroscopy is an analytical method used to detct the numbers of double and triple bonds present in dienes ,trienes and polyenes compounds.The energy corresponds to EM radiation in the ultraviolet (UV) region, 100-350 nm, and visible (VIS) regions 350-700 nm of the spectrum is known as UV spectrum.
UV spectroscopy is a technique used to analyze the composition of a sample by measuring its absorption or reflection of ultraviolet light. The sample is placed in a UV spectrophotometer and exposed to a range of UV wavelengths. The amount of light absorbed or reflected at each wavelength is recorded and plotted as a UV spectrum. This spectrum can be used to identify specific compounds in the sample, as each compound absorbs or reflects light at different wavelengths. This technique is widely used in fields such as chemistry, biology, and environmental science to analyze a variety of samples such as drugs, food, and water.
The branch of herbal medicine that describes the potentials and limitations of herbal drugs in the treatment of human diseases and should be practiced by physicians trained in herbalism.
Application of Nanotechnology in Natural ProductsMona Ismail
Nanoscience is the manipulation of materials at atomic, molecular and macromolecular scales, where properties differ significantly from those at a larger scale.
The word "Nano" is derived from the Greek word for “Dwarf”. It means a billionth. A nanometer is a billionth of a meter.
Herbal Medicine for Treatment of AsthmaMona Ismail
Asthma is a common chronic inflammatory disease of the airways characterized by variable and recurring symptoms, reversible airflow obstruction, and bronchospasm.
Flavonoids classification, isolation and identificationMona Ismail
Flavonoids are groups of polyphenolic compounds which are found in fruits, flowers, seeds & vegetable.
(named from the Latin word flavus meaning yellow, their colour in nature)
Plants produce a vast and diverse organic compounds, which do not appear to participate directly in growth and development.These substances traditionally referred to as secondary metabolites which terpenes are one of them.
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
Macroeconomics- Movie Location
This will be used as part of your Personal Professional Portfolio once graded.
Objective:
Prepare a presentation or a paper using research, basic comparative analysis, data organization and application of economic information. You will make an informed assessment of an economic climate outside of the United States to accomplish an entertainment industry objective.
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
Acetabularia Information For Class 9 .docxvaibhavrinwa19
Acetabularia acetabulum is a single-celled green alga that in its vegetative state is morphologically differentiated into a basal rhizoid and an axially elongated stalk, which bears whorls of branching hairs. The single diploid nucleus resides in the rhizoid.
A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...Levi Shapiro
Letter from the Congress of the United States regarding Anti-Semitism sent June 3rd to MIT President Sally Kornbluth, MIT Corp Chair, Mark Gorenberg
Dear Dr. Kornbluth and Mr. Gorenberg,
The US House of Representatives is deeply concerned by ongoing and pervasive acts of antisemitic
harassment and intimidation at the Massachusetts Institute of Technology (MIT). Failing to act decisively to ensure a safe learning environment for all students would be a grave dereliction of your responsibilities as President of MIT and Chair of the MIT Corporation.
This Congress will not stand idly by and allow an environment hostile to Jewish students to persist. The House believes that your institution is in violation of Title VI of the Civil Rights Act, and the inability or
unwillingness to rectify this violation through action requires accountability.
Postsecondary education is a unique opportunity for students to learn and have their ideas and beliefs challenged. However, universities receiving hundreds of millions of federal funds annually have denied
students that opportunity and have been hijacked to become venues for the promotion of terrorism, antisemitic harassment and intimidation, unlawful encampments, and in some cases, assaults and riots.
The House of Representatives will not countenance the use of federal funds to indoctrinate students into hateful, antisemitic, anti-American supporters of terrorism. Investigations into campus antisemitism by the Committee on Education and the Workforce and the Committee on Ways and Means have been expanded into a Congress-wide probe across all relevant jurisdictions to address this national crisis. The undersigned Committees will conduct oversight into the use of federal funds at MIT and its learning environment under authorities granted to each Committee.
• The Committee on Education and the Workforce has been investigating your institution since December 7, 2023. The Committee has broad jurisdiction over postsecondary education, including its compliance with Title VI of the Civil Rights Act, campus safety concerns over disruptions to the learning environment, and the awarding of federal student aid under the Higher Education Act.
• The Committee on Oversight and Accountability is investigating the sources of funding and other support flowing to groups espousing pro-Hamas propaganda and engaged in antisemitic harassment and intimidation of students. The Committee on Oversight and Accountability is the principal oversight committee of the US House of Representatives and has broad authority to investigate “any matter” at “any time” under House Rule X.
• The Committee on Ways and Means has been investigating several universities since November 15, 2023, when the Committee held a hearing entitled From Ivory Towers to Dark Corners: Investigating the Nexus Between Antisemitism, Tax-Exempt Universities, and Terror Financing. The Committee followed the hearing with letters to those institutions on January 10, 202
June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...
Ultraviolet spectroscopy (UV)
1.
2. Ultraviolet spectroscopy (UV) :
UV-Vis spectrophotometer measure absorption
of UV radiation (200-400 nm) and visible light
(400-800 nm) by molecule.
Promotion of electrons to higher energy levels
through irradiation of the molecule with
ultraviolet light. Provides mostly information
about the presence of conjugated π systems
and the presence of double and triple bonds.
3. It is called electronic spectroscopy, because the
energy absorbed (ΔE) is used to induce electron
transition i.e. one electron is promoted from
one molecular orbital to higher energy one.
UV-Visible spectrometry commonly used
because of its simplicity, versatility, speed,
accuracy and cost-effectiveness.
4.
5. Electronic spectrophotometer consist of the following
components:-
1-Radiation source: There are 2 different sources of
radiation;
A- tungsten lamp for scanning in the visible region.
B- hydrogen discharge tube for scanning in the UV
region.
2- Monochromator: which resolve polychromatic light
into a spectrum of monochromatic (i.e. of single
wavelength) light of the entire range.
6. 3- Sample and reference cells: the radiation
source is split into 2 beams;
The reference beam which passes through
reference cell containing solvent only.
Sample beam which passes through sample
solution.
4- Detector and recorder:
record absorbance against wavelength (λ) in nm.
This double beam technique is used to cancel out
solvent absorption between sample and reference
beams.
8. Solvent and Solution:-
Solvent must be transparent to UV-Vis radiation.
Common solvents are;
1- Polar solvents: Methanol, ethanol and water.
2- Non polar solvents: Hexane, cyclohexane.
3- Intermediate polarity: Ether and dioxane.
The UV cell (cuvette) is made of quartz (glass
absorb UV light) and has length of 1 cm.
9. The energy of a photon absorbed or emitted during a transition
from one molecular energy level to another is given by the
equation;
therefore, E= hc/λ
The shorter the wavelength, the greater the energy of
the photon and vice versa.
10. The energy supplied by the light will promote
electrons from their ground state orbitals to
higher energy, excited state orbitals or
antibonding orbitals.
Potentially, three types of ground state orbitals
may be involved:
i) σ (bonding) molecular as in
These contain normal bonding pairs of electrons.
The lowest energy level (it is the most stable).
11. ii) π (bonding) molecular orbital as in
These contain normal bonding pairs of electrons.
They are of higher energy than sigma
electrons.
iii) n (non-bonding) atomic orbital as in
Atomic orbitals of hetero atoms (N, O, or S)
which do not participate in bonding, they usually
occupy the highest level of ground state.
12. In addition, two types of anti-bonding orbitals
may be involved in the transition:
i) σ* (sigma star) orbital
ii) π* (pi star) orbital
The following electronic transitions can occur
by the absorption of ultraviolet and visible light:
σ to σ*
n to σ*
n to π*
π to π*
13.
14. In the exited state
σ electrons occupy an anti-bonding energy level
denotes as σ* and the transition is termed σ to σ*
transition.
π electrons occupy an anti-bonding energy level
denotes as π* and the transition is termed π to π*
transition.
n electrons occupy either π* or σ*.
15.
16. Both σ to σ* and n to σ* transitions require a great
deal of energy and therefore occur in the far
ultraviolet region (short λ) or weakly in the
region 180-240nm.
Consequently, saturated groups do not exhibit
strong absorption in the ordinary ultraviolet
region.
Transitions of the n to π* and π to π* type occur in
molecules with unsaturated centers; they require
less energy and occur at longer wavelengths than
transitions to σ* anti-bonding orbitals.
18. Some terms related to UV-Vis spectrophotometer:
1- Bathochromic shifts:
The shift of absorption to a longer wavelength due
to substitution or solvent effect (red shift)
2- Hypsochromic shifts:
The shift of absorption to a shorter wavelength due
to substitution or solvent effect (blue shift)
3- Hyperchromic effect:
It is increase in absorption intensity.
4- Hypochromic effect:
It is simply a decrease in the absorption intensity.
20. 5- Chromophore:
It is unsaturated group responsible for
electronic absorption e.g. C = C, C = O, NO2.
6- Auxochrome:
It is a saturated group, which when attached to a
chromophore alter both of wavelength λ and the
intensity of the maximum absorption.
These groups are generally characterized by having
unshared electron pairs e.g. -OH, -NH2, -Cl.
21. Factors affecting on Wavelength λ :-
1- Conjugation:-
E.↓λ↑more conjugated compounds
2- Substitution:-
E.↓λ↑more substituted compounds
Alkyl group substitution in benzene(λmax =256 nm)ring
cause slight bathochromic shift e.g. toluene has λmax at
261 nm.
Auxochrome e.g. –OH, -NH2, -OR … the interaction of
non-bounding electrons with π electrons of benzene
increase conjugation & cause bathochromic shift e.g.
aniline & phenol.
22. 3- Solvent:-
when the UV-Vis spectrum is recorded in different
solvents, The position and intensity of an absorption
band may shifted. For change to solvents of
increasing polarity the pattern of shifts will be as
follows;
1- Conjugated dienes & aromatic hydrocarbons display
very little solvent effects.
2- α,β- unsaturated carbonyl compounds show 2
different shifts;
a- The π π* band moves to longer wavelength
(bathochromic shift) red shift
b- The n π* band moves to shorter Wavelength
(hypsochromic shift) blue shift
23. Calculation of λmax
The first extensive set of rules was created by R. B.
Woodward and used extensively in the structure
elucidation of natural products.
Each type of diene or triene system is having a certain
fixed value at which absorption takes place; this
constitutes the Base value or Parent value.
The contribution made by various alkyl
substituents or ring residue, double bond
extending conjugation and polar groups such as –
Cl, -Br etc are added to the basic value to obtain
λmax for a particular compound
24. CONJUGATED DIENE CORRELATIONS:
1-Homoannular Diene:-
Cyclic diene having conjugated double bonds in
same ring.
2-Heteroannular Diene:-
Cyclic diene having conjugated double bonds in
different rings.
3-Endocyclic double bond:-
Double bond present in a ring.
25. 4- Exocyclic double bond: -
Double bond in which one of the doubly bonded
atoms is a part of a ring system.
Here Ring A has one exocyclic and endocyclic
double bond. Ring B has only one endocyclic
double bond.
26. i) Base value for homoannular diene = 253 nm
ii) Base value for heteroannular diene = 214 nm
iii) Alkyl substituent or Ring residue attached to the
parent diene = 5 nm
iv) Double bond extending conjugation = 30 nm
v) Exocyclic double bonds = 5 nm
vi) Polar groups:
1- OAc = 0 nm
2- OAlkyl = 6 nm
3- Cl, Br = 5 nm
27. e.g.
Base value = 214 nm
Ring residue = 3 x 5 = 15 nm
Exocyclic double bond = 1 x 5 = 5 nm
λmax = 214 + 15 +5 = 234 nm
29. 2. Alkyl substituent or Ring residue in α position = 10
nm
3. Alkyl substituent or Ring residue in β position = 12
nm
4. Alkyl substituent or Ring residue in γ and higher
positions = 18 nm
5. Double bond extending conjugation = 30 nm
6. Exocyclic double bonds = 5 nm
7. Homodiene compound = 39 nm
30. 8. Polar groups:
a) –OH in α position = 35 nm
–OH in β position = 30 nm
–OH in δ position = 50 nm
b) –OAc in α, β, γ, δ positions = 6 nm
c) –OMe in α position = 35 nm
–OMe in β position = 30 nm
–OMe in γ position = 17 nm
–OMe in δ position = 31 nm
d) –Cl in α position = 15 nm
–Cl in β position = 12 nm
e) –Br in α position = 25 nm
–Br in β position = 30 nm
f) –NR2 in β position = 95 nm
31. Base value = 215 nm
Double bond extending conjugation =1 x 30 = 30 nm
Exocyclic double bond = 5 nm
β- Substituents = 1 x 12 = 12 nm
δ- Substituents = 1 x 18 = 18 nm
λmax = 280 nm
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