North Maharashtra University 2009 B.Sc Chemistry Stereo-isomerism - Question Paper

c. Plane of Symmetry
d. Centre of Symmetry
e. Enantiomers and diastereomers
f. Conformation and configuration
g. Geometrical isomers
h. Racemic Modification
i. Dihedral angle
j. Dextro and leavo rotatory
3) Assign R or S Configuration for the subsequent
1) I 2) CHO
H–C–Cl Cl–C–H
Br CH3
3) CHO 4) H
H–C–OH ph–C–CH3
CH2OH OH
5) COOH 6) CH3
H–C–CH3 OH–C–H
OH D
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7) H 8) COOH
HO–C–CH3 H2N–C–H
Br CH3
9) F 10) I
O2N–C–C =CH D–C–Cl
C=N H
4) provide the structural formula of the subsequent.
a. Z-3-chloro-4-methyl-3-hexene
b. E-1-deuterio-2-chloro-propene
c. Z-2-bromo-2-butene
d. E-4-methyl-2-hexene
e. E-2-pentene
f. Z-2-phenyl-2-butene
g. E-3-hexene
h. Z-2-methyl-3-hexene
i. E-2-chloro-3-heptene
j. E-2-chloro-2-butene


ques. for 3marks.
1) provide the reasons.
a. Conformation of ethane can not be isolated.
b. Anti-conformation of n-butane is most stable conformation than any other
conformation.
c. Rotation about C=C (double bond) is hindered.
d. Ethylene and isobutylene do not show geometrical isomerism.
e. Tran’s isomers are more stable than cis isomers.
f. Chair Conformation is the most stable Conformation of cyclohexane.
g. Twist boat Conformation is more stable than boat Conformation.
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h. The equatorial methyl cyclohexane is more stable than axial methyl
cyclohexane by 1.8 Kcal/mole.
i. Staggered Conformation is most preferred than its eclipsed Conformation.
j. Racemic mixture is optically inactive.
k. The axial t-butyl cyclohexane does not exist.
2) Draw E & Z isomers of the subsequent & assign the Configuration name E or Z to
them.
a. 2-pentene
b. 2-phenyl-2-butene
c. 3-hexene
d. 2-methyl-3-hexene
e. 2-chloro-3-heptene
f. 2-chloro-2-butene
g. 1-chloro-1-bromo-1-propene
h. 1-chloro-2-bromo-1-propene
i. 3-chloro-2-pentene
j. 4-ethyl-5-n propyl-4-nonene
3) ans the subsequent.
a. discuss in brief E-Z nomenclature system.
b. discuss in brief Geometrical isomerism in oximes.
c. elaborate symmetry element? discuss any 1 with suitable example.
d. Draw chair & boat Conformation of cyclohexane & comment on their

Earning:   Approval pending.