Chapter 23

Write the IUPAC name of the following compound. CCOC(=O)c1ccccc1C(=O)Cl (a) ethyl-2-(chlorocarbonyl) benzoate (b) ethyl-2-(chlorocarbonyl) hexanoate (c) 2-(ethoxycarbony1) benzoyl chloride (d) none of these

CCCC(CC#N)CC#N (a) 3 -methyl hexane- \(1,2,3\)-tricarbonitrile (b) hexane-1, 2, 3 -tricarbonitrile (c)… # Assign the IUPAC name for the following compound. N#CCCC(CC#N)CC#N (a) 3 -methyl hexane- \(1,2,3\)-tricarbonitrile (b) hexane-1, 2, 3 -tricarbonitrile (c) 1,2 -bis (cyanomethyl) butanenitrile (d) 3-(cyanomethyl) hexane 1, 6-di-nitaite

The number of chiral carbon atoms in the given compound is are CCC1CCCCC1Br (a) 2 (b) 3 (c) 4 (d) 1

A compound with molecular formula \(\mathrm{C}_{7} \mathrm{H}_{16}\) shows optical isomerism. The compound will be (a) 2-methylhexane (b) 2,2 -dimethylpentane (c) 2,3 -dimethylpentane (d) none of these

Which of the following hydrocarbons has the lowest dipole moment? (a) CC=CC (b) \(\mathrm{CH}_{3}-\mathrm{C} \equiv \mathrm{C}-\mathrm{CH}_{3}\) (c) \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}=\mathrm{CH}_{2}\) (d) \(\mathrm{CH}_{2}=\mathrm{CH}-\mathrm{C} \equiv \mathrm{CH}\)

In the compound, \(\mathrm{CH}_{2}=\mathrm{CH}-\mathrm{CH}_{2}-\mathrm{CH}_{2}-\mathrm{C} \equiv \mathrm{CH}\), the \(\mathrm{C}_{2}-\mathrm{C}_{3}\) bond is of the type (a) \(\mathrm{sp}-\mathrm{sp}^{2}\) (b) \(s p^{3}-s p^{3}\) (c) \(\mathrm{sp}-\mathrm{sp}^{3}\) (d) \(\mathrm{sp}^{2}-\mathrm{sp}^{3}\)

An organic compound \(\mathrm{C}_{4} \mathrm{H}_{8} \mathrm{O}\) is found to be optically active. Which of the following is correct structure of the given compound? (a) \(\left(\mathrm{CH}_{3}\right)_{2} \mathrm{CHCHO}\) (b) \(\mathrm{CH}_{2}=\mathrm{CH}-\mathrm{CH}(\mathrm{OH}) \mathrm{CH}_{3}\) (c) \(\mathrm{CH}_{3} \mathrm{COCH}_{2} \mathrm{CH}_{3}\) (d) \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{CHO}\)

The number of optical isomers formed by hydrogenation of the compound, \(\left(\mathrm{CH}_{3}\right)_{2} \mathrm{C}=\mathrm{CHCH}_{3}\) are (a) 0 (b) 1 (c) 2 (d) 3

Which of the following can exhibit optical isomerism? (1) CC[N+](C)(C)C (2) ClC=C=C=CCl (3) CC1CC1 (4) (a) 1 and 2 (b) 2 and 4 (c) 3 only (d) 2 only

The number and type of bonds between two carbon atoms in \(\mathrm{CaC}_{2}\) are (a) one sigma and one \(\pi\) bond (b) one sigma and two \(\pi\) bonds (c) one sigma and one and a half \(\pi\) bonds (d) one sigma bond

Which of the following has the least hindered rotation about carbon-carbon bond? (a) ethane (b) ethylene (c) acetylene (d) hexachloroethane

The \(\mathrm{Cl}-\mathrm{C}-\mathrm{Cl}\) angle in \(1,1,2,2\)-tetrachloroethene and tetrachloromethane will be about (a) \(120^{\circ}\) and \(109.5^{\circ}\) (b) \(90^{\circ}\) and \(109.5^{\circ}\) (c) \(109.5^{\circ}\) and \(90^{\circ}\) (d) \(109.5^{\circ}\) and \(120^{\circ}\)

The compound with an isopropyl group is (a) \(2,2,3,3\)-tetramethylpentane (b) 2,2 -dimethylpentane (c) \(2,2,3\)-trimethylpentane (d) 2-methylpentane

The enolic form of acetone contains (a) 9 sigma bonds, 1 pi bond and 2 lone pair of electrons (b) 8 sigma bonds, 2 pi bonds and 2 lone pair of electrons (c) 10 sigma bonds, 1 pi bond and 1 lone pair of electrons (d) 9 sigma bonds, 2 pi bonds and 1 lone pair of electrons

How many chiral carbon atoms are present in 2,3 , 4-trichloropentane? (a) three (b) two (c) one (d) four

An optically active compound is (a) 1-bromobutane (b) \(\beta\)-bromobutyric acid (c) 2 -bromo-2-methylpropane (d) 1 -bromo-2-methylpropane

On monochlorination of 2 -methyl butane, the total number of chiral compounds is (a) 2 (b) 4 (c) 6 (d) 8

Which of the following compounds exhibit steroisomerism? (a) 2 -methylbutene- 1 (b) 3 -methylbutyne- 1 (c) 3 -methylbutanoic acid (d) 2 -methylbutanoic acid

The number of isomers for the compound with molecular formula \(\mathrm{C}_{2} \mathrm{BrClF}\) is (a) 3 (b) 4 (c) 5 (d) 6

Which of the following compounds will exhibit geometrical isomerism? (a) 1 -phenyl-2-butene (b) 3 -phenyl-1-butene (c) 2 -phenyl-1-butene (d) 1,1 -diphenyl-1-propene

Which of the following compounds will show geometrical isomerism? 1\. 2 -butene 2\. propene 3\. 1-phenylpropene 4\. 2 -methylbut-2-ene (a) 1,2 (b) 3,4 (c) \(1,2,3\) (d) 1,3

How many optically active stereoisomers are possible for butan- 2,3 -diol? (a) 1 (b) 2 (c) 3 (d) 4

The number of possible enantiomeric pairs than can be produced during monochlorination of 2 -methyl butane is (a) 2 (b) 3 (c) 4 (d) 1

The favoured conformation (Gauche, anti or eclipsed) for the molecule 1,2 -dichloro ethene 1,2 -ethanediol and propanaldehyde will be respectively (a) anti, eclipsed, gauche (b) anti, gauche, eclipsed (c) eclipsed, anti, gauche (d) Gauche, anti, eclipsed

Which is true regarding the \(\mathrm{HOCH}_{2}-(\mathrm{CHOH})_{4}\) \(-\mathrm{CH}_{2} \mathrm{OH} ?\) (1) the number of racemic mixtures will be four for the compound. (2) the total number of optical isomers is ten and number of meso isomer is two. (3) the total number of optical isomer is sixteen and number of meso isomer is zero. (4) the optically active isomers are eight while meso isomers are two. (a) 1,2 and 3 (b) 2,3 and 4 (c) 1,2 and 4 (d) 1 and 2 only

Consider the following compounds given below and select the correct statement. (I) CC1(C)CC(Br)CC1(C)C (II) CCC(C)C(C)=O (III) CC(F)(Cl)Cl (IV) CC1CCCCC1=O (a) except (I) all have stereogenic centre (b) all have stereogenic centre (c) all have plane of symmetry (d) only II and III have stereogenic centre

Match the following: List I List II 1\. \(\mathrm{CH}_{3} \mathrm{COOH}\) and \(\mathrm{HCOOCH}_{3}\) (i) metamers 2\. \(\mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{C} \equiv \mathrm{CH}\) and (ii) position isomers \(\mathrm{CH}_{3}-\mathrm{C}=\mathrm{C}-\mathrm{CH}_{3}\) 3\. \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{NH}_{2}\) and (iii) tautomers \(\mathrm{CH}_{3}-\mathrm{CH}\left(\mathrm{NH}_{2}\right)-\mathrm{CH}_{3}\) 4\. \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{OH}\) and \(\left(\mathrm{CH}_{3}\right)_{2} \mathrm{O}\) (iv) functional isomer The correct matching is: \(\begin{array}{llll}1 & 2 & 3 & 4\end{array}\) (a) (iii) (iv) (i) (iv) (b) (i) (ii) (iii) (iv) (c) (iii) (ii) (i) (iv) (d) (iv) (ii) (ii) (iv)

Consider the following statements: (1) racemic forms are not optically active but are resolvable (2) the presence of chiral atom is sufficient but not the necessary condition for enantiomer (3) meso compounds are inactive and are not resolvable (4) conformational enantiomers can be resolved Now select the correct statements. (a) 1,2 and 3 (b) 2,3 and 4 (c) 1,2 and 4 (d) \(1,2,3\) and 4

Which is incorrectly matched? Common name \(\quad\) IUPAC name (a) Vanillin 4-hydroxy-3-methoxybenzaldehyde (b) Protocatechual- \(\quad 2,3\)-dihydroxydehyde benzaldehyde (c) Adipic acid hexanl, 6-dioic acid (d) Pyruvic acid \(\quad\) cis-2-methylbut-2-enoic acid

How many structural and geometrical isomers are possible for dimethyl cyclohexane? (a) 3,3 (b) 3,6 (c) 6,6 (d) 6,3

Consider the following statements about chirality: 1\. molecules which are not superimposable on their mirror images are achiral 2\. a chiral molecule can have simple axis of symmetry 3\. a carbon atom to which four different species are attached is a chiral centre. 4\. a compound whose molecules are achiral exhibits optical activity Which of the statements given above are correct? (a) 1,2 and 4 (b) 2,3 and 4 (c) 2 and 3 (d) 1 and 4

The correct statements about the compounds A, Band \(\mathrm{C}\) are (A) COC(=O)C(O)C(O)C(=O)O (B) COC(=O)C(O)C(O)C(=O)O (C) COC(=O)C(O)C(O)C(=O)O (a) A and B are identical (b) \(\mathrm{A}\) and \(\mathrm{B}\) are enantiomers (c) A and C are enantiomers (d) A and B are diastereomers

Tautomerism is exhibited by which of the following compounds? (1) O=C1CCC(=O)C1 (2) ON=C=C1CCCCC1 (a) 1,2 and 3 (b) 1 and 3 (c) 1 and 2 (d) \(1,2,3\) and 4

Match the following: List I (Structure) List II (IUPAC name) 1\. \(\mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{CH}=\mathrm{CH}_{2}\) (i) 2-methylprop-1-ene 2 CC=C(C)C (ii) but-1-ene 3 . C=C(C)C (iii) cis-but-2-ene \(4 .\) CCC=C(C)C (iv) trans-but-2-ene The correct matching is: \(\begin{array}{ll}2 & 3 & 4\end{array}\) (a) (iii) (ii) (iv) (i) (b) (ii) (iii) (i) (iv) (c) (iii) (iv) (ii) (i) (d) (ii) (iv) (i) (iii)

Which of the following have asymmetric carbon atoms? 1\. \(\mathrm{ClCH}_{2}-\mathrm{CH}_{2} \mathrm{Br}\) 2\. \(\mathrm{CH}_{3}-\mathrm{CHCl}_{2}\) 3\. \(\mathrm{CH}_{3}-\mathrm{CH} \mathrm{DCl}\) 4\. \(\mathrm{CH}_{2} \mathrm{Br}-\mathrm{CHOH}-\mathrm{CH}_{3}\) (a) \(1,2,3\) (b) \(1,3,4\) (c) 2,3 (d) 3,4

Tautomerism is exhibited by 1 . OC=Cc1ccccc1 2 O=C1CC(=O)CC(=O)C1 3 . O=C1C=CC(=O)C=C1 4 O=C1CCCCC1=O (a) 1 and 2 (b) 1,3 and 4 (c) 1,2 and 4 (d) \(1,2,3\) and 4

Identify the correct statements (a) The stereisomers which are not mirror images are diastereomers. (b) Diasteteomers have the same physical properties like melting point and solubility (c) Cis isomer has higher melting point and lower solubility than the corresponding trans isomer (d) \(\mathrm{CH}_{3} \mathrm{COCH}_{2} \mathrm{COCH}_{3}\) exists more in enolic form in gaseous phase or in \(\mathrm{n}\) - hexane.

For each category of compounds the minimum number of carbons required for optical isomerism to be possible is given. Find the correct match (es). (a) Alkane \(-7\) (b) Alkene \(-6\) (c) Alkyl halide \(-4\) (d) Alkadiene - 7

Which of the following are incorrect statements? (a) IUPAC names of succinic acid is ethane 1,2 -dicarbolxylic acid. (b) Enantiomorphs possess identical biological properties. (c) Tetrahydrofuran is a heteroaromatic compound (d) Generally homologues are not isomers.

Tautomerism is exhibited by (a) O=C1C=CC(=O)C=C1 (b) OC=Cc1ccccc1 (c) O=C1CCCCC1=O (d) O=C1CCCC(=O)C1

Which of the following can show geometrical isomerism ? (a) But - 1- ene (b) But -2- ene (c) Hex - 3 - ene (d) 2- Chlorobut -2- ene

Keto-enol tautomerism is observed in (a) \(\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{COCH}_{3}\) (b) \(\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{CHO}\) (c) \(\mathrm{C}_{6} \mathrm{H}_{5}-\mathrm{CO}-\mathrm{CH}_{2}-\mathrm{CO}-\mathrm{CH}_{3}\) (d) NC1C=CC(=O)C=C1

A compound having molecular formula \(\mathrm{C}_{4} \mathrm{H}_{10} \mathrm{O}\) can show (a) Functional isomerism (b) Metamerism (c) Position isomerism (d) Optical isomerism

Which of the following does not exhibit tautomerism? (a) CCOC(=O)C(C)C(C)O (b) \(\mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{NO}_{2}\) (c) CCOC(=O)C(C)C(C)O (d) \(\mathrm{CH}_{3}-\mathrm{NH}-\mathrm{CO}-\mathrm{CH}_{3}\)

Enol content of \(\mathrm{CH}_{3}-\mathrm{CO}-\mathrm{CH}_{2}-\mathrm{CO}-\mathrm{CH}_{3}\) will be maximum in which of the solvents? (a) Water (b) \(\mathrm{n}\) - hexane (c) \(\mathrm{CH}_{3}-\mathrm{COOH}\) (d) Aqueous \(\mathrm{HCl}\)

Following pair of structures represents CC1C=CCCC1Br CC1CCCC(Br)C1 (a) pair of enantiomers (b) pair of anomers (c) pair of diastereomers (d) all of the above

Match the following \begin{tabular}{ll} \hline Column-I & Column-II \\ \hline (a) Enantiomers & (p) Equilibrium mixture \\ (b) Diastereomers & (q) Mirror images \\ (c) Meso isomer & (r) Non- mirror images \\ (d) Tautomers & (s) Non- superimposable \\ & (t) Stereo isomer \\ \hline \end{tabular}

Match the following Column-I (a) \(\mathrm{CH}_{3} \mathrm{CHDT}\) (b) \(\mathrm{CH}_{3} \mathrm{CH}(\mathrm{OH}) \mathrm{CH}(\mathrm{OH}) \mathrm{C}_{2} \mathrm{H}_{5}\) (c) \(\mathrm{CH}_{3} \mathrm{CH}(\mathrm{OH}) \mathrm{CH}(\mathrm{OH}) \mathrm{CH}_{3}\) (d) Column-II (p) No optical isomer (q) Two optical isomers (r) Four optical isomers (s) Three optical isomers (t) Two asymmetric carbon atoms.

(Assertion): The reaction of \(\mathrm{HCN}\) with \(\mathrm{EtCH}(\mathrm{Me})\) \(\mathrm{C}^{13} \mathrm{HO}\) gives two optically active isomers in unequal amounts. (Reason): Formation of cyanohydrins at \(\mathrm{C}-13\) gives rise to \(\mathrm{d}\) and \(\mathrm{l}\) isomers.

(Assertion): An optically active molecule must be asymmetric. (Reason): Asymmetric molecules will have nonsuperposable mirror image.