In which of the below reaction do we find $\mathrm{\alpha },\mathrm{\beta }-$unsaturated carbonyl compounds undergoing a ring closure reaction with conjugated dienes?

• Perkin reaction

• Diels-Alder reaction

• Claisen rearrangement

• Hofmann reaction

42.

IUPAC name of the compound

• 5-methyl-4-iso propyl-6, 6' diethyloctane

• 3,3-dimethyl, 3-ethyl-5-isopropyl octane

• 3,3-diethyl-4-methyl-5-(1,1-dimethyl) octane

• 3,3-diethyl-4-methyl-5-(1'-methylethyl) octane

Consider the following carbocations,

$$\begin{gathered} \left(\mathrm{I}\right) {\mathrm{C}}_6{\mathrm{H}}_5\stackrel{+}{\mathrm{C}}{\mathrm{H}}_2 \left(\mathrm{II}\right) {\mathrm{C}}_6{\mathrm{H}}_5{\mathrm{CH}}_2\stackrel{+}{\mathrm{C}}{\mathrm{H}}_2 \\ \left(\mathrm{III}\right) {\mathrm{C}}_6{\mathrm{H}}_5\stackrel{+}{\mathrm{C}}{\mathrm{HCH}}_3 \left(\mathrm{IV}\right) {\mathrm{C}}_6{\mathrm{H}}_5\stackrel{+}{\mathrm{C}}({\mathrm{CH}}_3{)}_2 \end{gathered}$$

The correct sequence of the stability of these is

• II < I < III < IV

• II < III < I < IV

• III < I < II < IV

• IV < III < I < II

2 2-dichloro propane on hydrolysis yields

• acetone

• 2, 2-propane diol

• isopropyl alcohol

• acetaldehyde

For synthesis of 1-butene, CH3MgI should be treated with

• propene

• 2-chloropropene

• allyl chloride

• ethyl chloride

Ethylidene dichloride is obtained by the reaction of excess of HCl with

• ethylene

• acetylene

• propene

• methane

Hardening of oil is done by

• dehydrogenation

• hydrogenation

• dehydrohalogenation

• dehydration

Which one of the following compounds will react with methyl magnesium iodide ?

• CH₃CH₂CH₂CH₂CH₃

• ${\mathrm{CH}}_3\mathrm{CH}=\mathrm{CH}-\mathrm{CH}={\mathrm{CH}}_2$

• ${\mathrm{CH}}_3-\mathrm{C}\equiv \mathrm{C}-{\mathrm{CH}}_2{\mathrm{CH}}_3$

• ${\mathrm{CH}}_3{\mathrm{CH}}_2{\mathrm{CH}}_2\mathrm{C}\equiv \mathrm{CH}$

Which of the following compounds do not give different isomers on monochlorination?

• Neo-pentane

• n-butane

• Iso-butane

• Iso-pentane