The document discusses UV spectroscopy and the different types of bands that can be observed. It explains that compounds with higher conjugation absorb at lower wavelengths due to a smaller energy gap between orbitals. Four main bands are described: K-band observed in conjugated double bonds with high intensity; R-band in carbonyl compounds with low intensity as it is a forbidden transition; B-band in aromatic/heteroaromatic compounds typically between 230-270nm; and E-band in benzenoid systems where benzene shows a strong band at 184nm.
This document discusses ultraviolet-visible (UV-Vis) spectroscopy. It begins by defining spectroscopy and describing the electromagnetic radiation spectrum. It then focuses on UV-Vis spectroscopy, explaining that it involves electronic transitions in molecules caused by the absorption of ultraviolet or visible light. The major electronic transitions that can occur are defined, including σ → σ*, n → σ*, π → π*, and n → π* transitions. Factors that affect these transitions, such as conjugation, are also discussed. Real-world examples of molecular structures and the transitions they undergo are provided.
The document discusses various spectroscopic methods used in organic chemistry including UV-Visible, Infrared, Nuclear Magnetic Resonance, and Mass Spectroscopy. It explains the basic principles of spectroscopy such as how electromagnetic radiation interacts with molecules by absorption or emission of energy. The document also provides details on the instrumentation used in spectroscopy including spectrophotometers and spectrographs.
The document discusses green chemistry as a remedy for environmental pollution. It defines green chemistry as the generation of new products and processes that reduce or eliminate hazardous materials. The need for green chemistry is explained by new environmental problems, harmful side effects of some chemicals like DDT, and accidents. Advantages of green chemistry include being eco-friendly, energy efficient, producing less waste and safer products. The principles of green chemistry focus on preventing waste, improving atom economy in synthesis, using safer solvents and feedstocks, and designing for energy efficiency and degradation. Examples are given around safer chemical design and replacing hazardous solvents.
The document discusses UV spectroscopy and the different types of bands that can be observed. It explains that compounds with higher conjugation absorb at lower wavelengths due to a smaller energy gap between orbitals. Four main bands are described: K-band observed in conjugated double bonds with high intensity; R-band in carbonyl compounds with low intensity as it is a forbidden transition; B-band in aromatic/heteroaromatic compounds typically between 230-270nm; and E-band in benzenoid systems where benzene shows a strong band at 184nm.
This document discusses ultraviolet-visible (UV-Vis) spectroscopy. It begins by defining spectroscopy and describing the electromagnetic radiation spectrum. It then focuses on UV-Vis spectroscopy, explaining that it involves electronic transitions in molecules caused by the absorption of ultraviolet or visible light. The major electronic transitions that can occur are defined, including σ → σ*, n → σ*, π → π*, and n → π* transitions. Factors that affect these transitions, such as conjugation, are also discussed. Real-world examples of molecular structures and the transitions they undergo are provided.
The document discusses various spectroscopic methods used in organic chemistry including UV-Visible, Infrared, Nuclear Magnetic Resonance, and Mass Spectroscopy. It explains the basic principles of spectroscopy such as how electromagnetic radiation interacts with molecules by absorption or emission of energy. The document also provides details on the instrumentation used in spectroscopy including spectrophotometers and spectrographs.
The document discusses green chemistry as a remedy for environmental pollution. It defines green chemistry as the generation of new products and processes that reduce or eliminate hazardous materials. The need for green chemistry is explained by new environmental problems, harmful side effects of some chemicals like DDT, and accidents. Advantages of green chemistry include being eco-friendly, energy efficient, producing less waste and safer products. The principles of green chemistry focus on preventing waste, improving atom economy in synthesis, using safer solvents and feedstocks, and designing for energy efficiency and degradation. Examples are given around safer chemical design and replacing hazardous solvents.
The document discusses chemistry problems and solutions presented by B.Sateesh Kumar, an assistant professor of chemistry at GDC(M)-SKLM. It includes 3 chemistry problems involving the products of reactions and Kumar's explanations of the major products formed. Specifically, it discusses hydrogenolysis to deprotect functional groups on amino acids, the reduction of an epoxide to an alcohol using LAH, and a two-step reaction sequence involving a Schmidt reaction and Boc protection.
DIBAL-H is a commercially available selective reducing agent that can reduce esters and nitriles to the corresponding aldehydes. It is prepared by heating triisobutylaluminum, which induces beta hydride elimination to form DIBAL-H and isobutene. DIBAL-H selectively reduces esters to aldehydes at low temperatures through a tetrahedral intermediate. Hydrolytic workup of this intermediate then yields the desired aldehyde products. The document provides an introduction to DIBAL-H including its preparation, applications in organic synthesis, and how it differs from other reducing agents like LiAlH4.
The document discusses sodium cyanoborohydride (NaBH3CN), including its preparation from sodium borohydride and hydrogen cyanide, properties such as being a less reactive reducing agent than sodium borohydride, solubility in solvents like THF and methanol, and ability to reduce protonated aldehydes and ketones at pH 3 but not neutral aldehydes and ketones. Main applications of sodium cyanoborohydride include its use as a reducing agent in organic synthesis reactions.
The document discusses chemistry problems and solutions presented by B.Sateesh Kumar, an assistant professor of chemistry at GDC(M)-SKLM. It includes 3 chemistry problems involving the products of reactions and Kumar's explanations of the major products formed. Specifically, it discusses hydrogenolysis to deprotect functional groups on amino acids, the reduction of an epoxide to an alcohol using LAH, and a two-step reaction sequence involving a Schmidt reaction and Boc protection.
DIBAL-H is a commercially available selective reducing agent that can reduce esters and nitriles to the corresponding aldehydes. It is prepared by heating triisobutylaluminum, which induces beta hydride elimination to form DIBAL-H and isobutene. DIBAL-H selectively reduces esters to aldehydes at low temperatures through a tetrahedral intermediate. Hydrolytic workup of this intermediate then yields the desired aldehyde products. The document provides an introduction to DIBAL-H including its preparation, applications in organic synthesis, and how it differs from other reducing agents like LiAlH4.
The document discusses sodium cyanoborohydride (NaBH3CN), including its preparation from sodium borohydride and hydrogen cyanide, properties such as being a less reactive reducing agent than sodium borohydride, solubility in solvents like THF and methanol, and ability to reduce protonated aldehydes and ketones at pH 3 but not neutral aldehydes and ketones. Main applications of sodium cyanoborohydride include its use as a reducing agent in organic synthesis reactions.
2. Useful to
• II & III BSc CHEMISTRY STUDENTS
• IIT JAM
• CU-CET
• PG-CETS
• CSIR-NET
3. 1. In the EMR spectrum I.R region is
[EMR స్పెక్ట్రంలో I.R ప్ర ంతం]
a. 200-400Cm-1
b. 4000-600Cm-1
c. Both
d. 600-4000
B.SATEESH KUMAR , CHEMISTRY , GDC(M)-SKLM
4. 2. I.R radiation is obtained from
[I.R రేడియేషన్ దేని న ండి పందబడుత ంది]
a. Sodium vapour lamp
b. Nernst glower
c. Hydrogen discharge lamp
d. None of the above
B.SATEESH KUMAR , CHEMISTRY , GDC(M)-SKLM
All answers in Red [అన్ని సమాధానాలు ఎరుపు రంగులో ఉనాియి]
5. 3. The UV radiation region use for organic compound
is
[క్టర్బన సమ్మేళనాల కోసం ఉపయోగంచే UV రేడియేషన్
ప్ర ంతం]
a.400-800nm
b.150-200nm
c.200-400nm
d.None
B.SATEESH KUMAR , CHEMISTRY , GDC(M)-SKLM
6. 4. Which one of the following is an example of
Chromophore
[కంది వ్టిలో ఏది కోో మోఫో రక్టు ఉదాహర్ణ]
a. -OH
b. -CH3
c. -CHO
d. -NH2
B.SATEESH KUMAR , CHEMISTRY , GDC(M)-SKLM
7. 5. Which of the following adsorbs at higher
wavelength in U.V
[U.V క్ంతిని అధిక్ట తర్ంగదైర్్యం వదద కంది వ్టిలో ఏది
శోషిoచ క్టుంట ంది]
a. CH3CH=CHCHO
b. PhCHO
c. Ph-CH=CHCHO
d. PhCH2CH2CHO
B.SATEESH KUMAR , CHEMISTRY , GDC(M)-SKLM
8. 6. Which of the following adsorbs I.R radiation
between 3300-3500cm-1
[కంది వ్టిలో I.R రేడియేషన్ 3300-3500cm-1 మధ్య
శోషి౦చ కొన న ]
a. CH3CHO
b. CH3OCH3
c. CH3NH2
d. CH2=CH2
B.SATEESH KUMAR , CHEMISTRY , GDC(M)-SKLM
9. 7. Vinyl group is an example of
[వినైల్ సమూహం దేనిక ఉదాహర్ణ]
a. Auxochrome
b. Chromophore
c. Both
d. None
B.SATEESH KUMAR , CHEMISTRY , GDC(M)-SKLM
10. 8. Among the following which absorbs higher
frequency
[కంది వ్టిలో అధిక్ట పౌన .పునాయనిి గోహంచేది]
a. C-C
b. C=C
c. C=O
d. C≡C
B.SATEESH KUMAR , CHEMISTRY , GDC(M)-SKLM
11. 9. The I.R absorption streching frequency range of
carbonyl group is
[క్రబబనిల్ సమూహం యొక్టక I.R శోషణ స్గే క్టంపన
పౌనపునయం పరధి]
a. 1650-1750 Cm-1
b. 1000-1200 Cm-1
c. 3500-3600 Cm-1
d. 2500-3000 Cm-1
12. 10. Chromophore among the following is
[కంది వ్టిలో కోో మోఫో ర సమూహం ఏది]
a. -COCH3
b. -NH2
c. -CH3
d. -OH
B.SATEESH KUMAR , CHEMISTRY , GDC(M)-SKLM
13. 11. RCONH2 and RNH2 can be distinguished by
[RCONH2 మరయు RNH2 లన వేర్ు చేయవచ ు]
a. U.V
b. I.R
c. BOTH
d. NONE
B.SATEESH KUMAR , CHEMISTRY , GDC(M)-SKLM
14. 12. Auxochrome among the following is
[కంది వ్టిలో ఆకోోకోో మ్]
a. -Ph
b. -CHO
c. -NH2
d. >C=S
B.SATEESH KUMAR , CHEMISTRY , GDC(M)-SKLM
15. 13. Aniline in the presence of acid exhibits
[ఆమల సమక్షంలో అనిలిన్ ఏ షిఫ్ట్ న చూపున ]
a. Bathochromic shift
b. Hypsochromic shift
c. Hypochromic shift
d. Hyper chromic shift
B.SATEESH KUMAR , CHEMISTRY , GDC(M)-SKLM
16. 14. Formyl group is a
[ఫ్ర్మేల్ సమూహం ఒక్ట]
a. Auxochrome
b. Chromophore
c. Both
d. None
B.SATEESH KUMAR , CHEMISTRY , GDC(M)-SKLM
17. 15. Finger print region is
[ఫింగర పిరంట్ ప్ర ంతం]
a. 1400-4000Cm-1
b. 910-1400Cm-1
c. 2200-4000Cm-1
d. None
B.SATEESH KUMAR , CHEMISTRY , GDC(M)-SKLM