Multiple Choice QuestionsIn an SN1 reaction on chiral centres, there is
100% racemisation
inversion more than retention leading to partial racemization
100% retention
100% retention
The order of reactivity of phenyl magnesium bromide (phMgBr) with the following compounds.
III > II> I
II > I > III
I > III > II
I > III > II
D.
I > III > II
Since alkyl group has +I -effect and aryl group has +R - effect, thus, greater the number of alkyl and aryl groups attached to the carbonyl group, its reactivity towards nucleophilic addition reaction. Secondly, as the steric crowding on carbonyl group increases, the reactivity decreases accordingly.
therefore, correct reactivity order for reaction with PhMgBr is
The IUPAC name of the following compound
trans - 2- chloro - 3 - iodo - 2 - pentene
cis - 3- iodo - 4- chloro - 3- pentene
trans - 3- iodo - 4- chloro - 3- pentene
trans - 3- iodo - 4- chloro - 3- pentene
Consider the reactions
The mechanisms of reactions (i) and (ii) are respectively
SN1 and SN2
SN1 and SN1
SN2 and SN2
SN2 and SN2
In the reaction with HCl, an alkene reacts in accordance with the markownikoff's rule, to give a product 1-chloro -1- methylcyclohexane. The possible alkane is
(a) and (b)
(a) and (b)
2,3 -dimethyl - 2- butene can be prepared by heating which of the following compounds with a strong acid?
(CH3)2CH-CH(CH)3-CH=CH2
(CH3)3C-CH=CH2
(CH3)2C =CH-CH2-CH3
(CH3)2C =CH-CH2-CH3
Which one is most reactive towards SN1 reaction?
C6H5CH(C6H5)Br
C6H5CH(CH3)Br
C6H5C(CH3)(C6H5)Br
C6H5C(CH3)(C6H5)Br
In the following reaction, 
the product 'X' is
C6H5CH2OCH2C6H5
C6H5CH2OH
C6H5CH3
C6H5CH3
Which of the following reactions is an example of nucleophilic substitution reaction?
RX + KOH → ROH + KX
2RX + 2Na → R- R
RX + H2 → RH + HX
RX + H2 → RH + HX
Consider the following reaction,
the product Z, is
CH2 = CH2
CH3CH2-O-CH2-CH3
CH3-CH2-O-SO3H
CH3-CH2-O-SO3H
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