Chapter 8

Organometallic reactions can be classified into fundamental reaction types. Classify the (a) Ligand insertion (b) Ligand dissociation (c) Reductive elimination (d) Oxidative addition

Consider the relative basicity of these three amines. Which statement is true? (a) Cyclohexylamine is the strongest base and aniline is the weakest base (b) Cyclohexylamine is the strongest base and 4 -nitroaniline is the weakest base (c) Aniline is the strongest base and cyclohexylamine is the weakest base (d) Nitroaniline is the strongest base and cyclohexylamine is the weakest base

What is not the name for the following compound? (a) 2 -Acetaldehyde (b) propanone (c) acetone (d) dimethyl ketone

Which of the following is most reactive towards aqueous HBr? (a) 1-Phenyl-2-propanol (b) 1-Phenyl-1-propanol (c) 3-Phenyl-1-propanol (d) 2-Phenyl-1-propanol

Ethylbenzene when treated with chlorine in presence of light mainly gives (a) \(\beta\) -phenylethyl chloride (b) \(\alpha\) -phenylethyl chloride (c) o-chloroethyl benzene (d) o-and p-chloroethylbenzene

Methanoic acid is heated with Conc. \(\mathrm{H}_{2} \mathrm{SO}_{4}\), to form (a) \(\mathrm{CO}\) (b) \(\mathrm{CO}_{2}\) (c) \(\mathrm{CH}_{4}\) (d) \((\mathrm{COOH})_{2}\)

When ethane-1,2-dioic acid is heated with Conc. \(\mathrm{H}_{2} \mathrm{SO}_{4^{\prime}}\) it gives (a) \(\mathrm{CO}+\mathrm{HCOOH}\) (b) \(\mathrm{CO}_{2}+\mathrm{HCOOH}\) (c) \(\mathrm{CO}+\mathrm{CO}_{2}+\mathrm{HCOOH}\) (d) \(\mathrm{CO}+\mathrm{CO}_{2}+\mathrm{H}_{2} \mathrm{O}\)

When sodium formate is heated with soda lime, we get (a) \(\mathrm{CH}_{4}\) (b) \(\mathrm{H}_{2}\) (c) sodium oxalate (d) no action

Sodium formate is heated at \(360^{\circ} \mathrm{C}\) to give (a) \(\mathrm{CO}\) (b) \(\mathrm{CO}_{2}\) (c) sodium oxalate (d) no action

Nitrobenzene can be reduced to aniline by (i) \(\mathrm{H}_{2} / \mathrm{Ni}\) (ii) \(\mathrm{Sn} / \mathrm{HCl}\) (iii) \(\mathrm{Zn} / \mathrm{NaOH}\) (iv) \(\mathrm{LiAlH}_{4}\) (a) i, ii and iii (b) \(\mathrm{i}\) and ii (c) i, ii and iv (d) only ii

1-Methylcyclopentene can be converted into 2-methylcyclopentanol by (a) acid-catalyzed hydration (b) hydroboration oxidation (c) epoxide formation followed by reduction with LiAlH \(_{4}\) (d) oxymercuration-demercuration

Predict the nature of \(\mathrm{P}\) in the following reaction \(\mathrm{CH}_{3} \mathrm{C} \equiv \mathrm{CCH}_{3} \frac{\mathrm{NaNH}_{2} \text { /inert solvent }}{\text { heat }}{\longrightarrow} \mathrm{P}\)

Arrange the following alcohols in order of increasing ease of dehydration (i) \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{OH}\) (ii) \(\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{CH}_{2} \mathrm{OH}\) (iii) \(\mathrm{Cl}_{3} \mathrm{CCH}_{2} \mathrm{OH}\) (iv) \(\mathrm{F}_{3} \mathrm{CCH}_{2} \mathrm{OH}\) (a) \(\mathrm{ii}<\mathrm{i}<\mathrm{iv}<\mathrm{iii}\) (b) \(\mathrm{iv}<\mathrm{iii}<\mathrm{ii}<\mathrm{i}\) (c) \(\quad\) iv \(<\) iii \(

1,2-Diethylbenzene on ozonolysis gives..........different products (a) 1 (b) 2 (c) 3 (d) 4

When o-hydroxybenzaldehyde is heated with ethanoic anhydride in the presence of sodium ethanoate, compound formed during the reaction is

A new carbon-carbon bond is formed in (i) Aldol condensation (ii) Kolbe's reaction (iii) Reimer-Tiemann reaction (iv) Wurtz Fittig reaction (a) i, iii (b) ii, iii (c) i, iii, iv (d) All of these

\(\mathrm{Me}_{2} \mathrm{CHOCMe}_{3} \stackrel{\mathrm{HI}}{\longrightarrow} \mathrm{X}+\mathrm{Y}\) Predict the nature of product and the type of reaction involved in their formation. (a) \(\mathrm{Me}_{2} \mathrm{CHI}\) and \(\mathrm{Me}_{3} \mathrm{COH}\), formed by \(\mathrm{S}_{\mathrm{N}} 1\) reaction (b) \(\mathrm{Me}_{2} \mathrm{CHI}\) and \(\mathrm{Me}_{3} \mathrm{CI}\), formed by \(\mathrm{S}_{\mathrm{N}} 1\) reaction (c) \(\mathrm{Me}_{2} \mathrm{CHI}\) and \(\mathrm{Me}_{3} \mathrm{COH}\), formed by \(\mathrm{S}_{\mathrm{N}} 2\) reaction (d) \(\mathrm{Me}_{2} \mathrm{CHOH}\) and \(\mathrm{Me}_{3} \mathrm{CI}\), formed by \(\mathrm{S}_{\mathrm{N}} 2\) reaction

The ethereal linkage \((-C-O-C-)\) is cleaved by (a) \(\mathrm{HBr}\) (b) \(\mathrm{HNO}_{3}\) (c) Both (a) and (b) (d) None

Products \(\left(\mathrm{P}_{2}\right)\) \(\stackrel{\text { anhy. } \mathrm{HI}}{\longleftarrow}\left(\mathrm{CH}_{3}\right)_{3} \mathrm{C}-\mathrm{O}-\mathrm{CH}_{3} \stackrel{\text { Conc. } \mathrm{HI}}{\longrightarrow}\) Products \(\left(\mathrm{P}_{1}\right)\) The products \(\mathrm{P}_{1}\) and \(\mathrm{P}_{2}\) respectively are (a) \(\left(\mathrm{CH}_{3}\right)_{3} \mathrm{COH}+\mathrm{CH}_{3} \mathrm{I}\) and \(\left(\mathrm{CH}_{3}\right)_{3} \mathrm{CI}+\mathrm{CH}_{3} \mathrm{OH}\) (b) \(\left(\mathrm{CH}_{3}\right)_{3} \mathrm{CI}+\mathrm{CH}_{3} \mathrm{OH}\) and \(\left(\mathrm{CH}_{3}\right)_{3} \mathrm{COH}+\mathrm{CH}_{3} \mathrm{I}\) (c) \(\left(\mathrm{CH}_{3}\right)_{3} \mathrm{CI}+\mathrm{CH}_{3} \mathrm{OH}\) in both cases (d) \(\mathrm{CH}_{3} \mathrm{I}\) and \(\left(\mathrm{CH}_{3}\right)_{3} \mathrm{COH}\) in both cases

Cyclobutylethene is treated with dil. \(\mathrm{H}_{2} \mathrm{SO}_{4}\) to form (a) 2 -cyclobutylethanol (b) 1-cyclobutyl-2-ethanol (c) 2 -methylcyclopentanol (d) 1 -methylcyclopentanol

The decreasing order of acidic character of the compounds is \(\mathrm{CH}_{3} \mathrm{C} \equiv \mathrm{CH}, \mathrm{MeOH}, \mathrm{Me}_{2} \mathrm{CHOH}, \mathrm{Me}_{3} \mathrm{COH}, \mathrm{H}_{2} \mathrm{O}\) (a) \(\mathrm{CH}_{3} \mathrm{C} \equiv \mathrm{CH}>\mathrm{Me}_{3} \mathrm{COH}>\mathrm{Me}_{2} \mathrm{CHOH}>\mathrm{MeOH}>\mathrm{H}_{2} \mathrm{O}\) (b) \(\mathrm{MeOH}>\mathrm{Me}_{2} \mathrm{CHOH}>\mathrm{Me}_{3} \mathrm{COH}>\mathrm{H}_{2} \mathrm{O}>\mathrm{CH}_{3} \mathrm{C} \equiv \mathrm{CH}\) (c) \(\mathrm{Me}_{3} \mathrm{COH}>\mathrm{Me}_{2} \mathrm{CHOH}>\mathrm{MeOH}>\mathrm{H}_{2} \mathrm{O}>\mathrm{CH}_{3} \mathrm{C} \equiv \mathrm{CH}\) (d) \(\mathrm{MeOH}>\mathrm{H}_{2} \mathrm{O}>\mathrm{Me}_{2} \mathrm{CHOH}>\mathrm{Me}_{3} \mathrm{COH}>\mathrm{CH}_{3} \mathrm{C} \equiv \mathrm{CH}\)

Arrange the following in the decreasing order of acidic strength (i) Phenol (ii) p-nitrophenol (iii) \(\mathrm{m}\) -cresol (iv) \(\mathrm{p}\) -cresol (a) \(\mathrm{ii}>\mathrm{iii}>\mathrm{iv}>\mathrm{i}\) (b) \(\mathrm{ii}>\mathrm{i}>\mathrm{iii}>\mathrm{iv}\) (c) \(\mathrm{ii}>\mathrm{i}>\mathrm{iv}>\) iii (d) \(\mathrm{iii}>\mathrm{iv}>\mathrm{ii}>\mathrm{i}\)

Which of the following will be most acidic (a) o-Aminophenol (b) p-Aminophenol (c) m-Aminophenol (d) None of these

Arrange the following in increasing acidic character (i) Phenol (ii) m-nitrophenol (iii) \(\mathrm{m}\) -chlorophenol (iv) \(\mathrm{m}\) -cresol (a) iv \(<\mathrm{i}<\mathrm{iii}<\mathrm{ii}\) (b) iv \(<\mathrm{i}<\mathrm{ii}<\mathrm{iii}\) (c) \(i<\) iv \(<\) iii \(<\) ii (d) iii \(<\mathrm{ii}<\mathrm{iv}<\mathrm{i}\)

Which of the following statement is true regarding amount of \(\mathrm{AlCl}_{3}\) required during Friedel-Craft acetylation using acetyl chloride or acetic anhydride? (a) Both require same amount (b) Acetylation with acetyl chloride requires more amount (c) Acetylation with acetic anhydride requires more amount (d) Nothing is definite

Which of the following gives effervescenes of \(\mathrm{CO}_{2}\) with \(\mathrm{NaHCO}_{3}\) solution? (a) \(\mathrm{HCOOH}\) (b) \(2,4,6\) -trinitrophenol (c) Both (a) and (b) (d) None of these

\(2,4,6\) -Trinitrophenol can be prepared in good yield (a) by the nitration of 2,4 -dinitrochlorobenzene (b) by the nitration of 2,4 -dinitrophenol (c) by both (a) and (b) (d) neither by (a) nor by (b)

Which of the following has highest and lowest hydration equilibrium constant? \(\mathrm{HCHO}, \mathrm{CH}_{3} \mathrm{CHO}, \mathrm{CH}_{3} \mathrm{COCH}_{3}\) (a) HCHO-Highest, \(\mathrm{CH}_{3}\) CHO-Lowest (b) \(\mathrm{CH}_{3}\) CHO-Highest, HCHO-Lowest (c) HCHO-Highest, \(\mathrm{CH}_{3} \mathrm{COCH}_{3}\) -Lowest (d) \(\mathrm{CH}_{3} \mathrm{COCH}_{3}\) -Highest, HCHO-Lowest

\(\mathrm{CH}_{3} \mathrm{COCH}_{2} \mathrm{Cl} \stackrel{\mathrm{OH}^{-}, \mathrm{Cl}_{2}}{\longrightarrow}\) Product \(\mathrm{P}\) is (a) \(\mathrm{ClCH}_{2} \mathrm{COCH}_{2} \mathrm{Cl}\) (b) \(\mathrm{CH}_{3} \mathrm{COCHCl}_{2}\) (c) Both (a) and (b) (d) \(\mathrm{ClCH}_{2} \mathrm{COOH}+\mathrm{CH}_{3} \mathrm{Cl}\)

Propanal and propanone, both have same molecular formula \(\left(\mathrm{C}_{3} \mathrm{H}_{6} \mathrm{O}\right)\), what do you expect about their boiling points? (a) Both have same boiling point. (b) Boiling point of propanal is higher than the boiling point of propanone. (c) Boiling point of propanal is lower than the boiling point of propanone. (d) Nothing can be predicted.

In dilute aqueous solution, formaldehyde exists as (a) Formaldehyde (b) Paraldehyde (c) Trioxymethylene (d) Methyleneglycol

The major driving force for the hydration of chloral is (a) less steric hinderance in the product (b) less force of repulsion in the product (c) hydrogen bonding in the product (d) electronegativity of the three chlorine atoms

Fehling's solution can be used for distinguishing between (a) \(\mathrm{CH}_{3} \mathrm{CHO}\) and \(\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{CHO}\) (b) \(\mathrm{CH}_{3} \mathrm{CHO}\) and \(\mathrm{CH}_{3} \mathrm{COCH}_{2} \mathrm{OH}\) (c) Both (a) and (b) (d) None of these

Which of the following is least reactive with a nucleophile? (a) Methanal (b) Propanone (c) 3-Pentanone (d) 2 -Pentanone

Aldehydic group can be protected (a) by acetal formation against alkaline oxidizing agents. (b) by mercaptal formation against acidic oxidizing agents. (c) both (a) and (b) (d) none of the above

Which is least reactive towards addition of HCl? (a) \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}=\mathrm{CH}_{2}\) (b) \(\mathrm{CH}_{2}=\mathrm{CH}-\mathrm{CH}=\mathrm{CH}_{2}\) (c) \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{C} \equiv \mathrm{CCH}_{3}\) (d) \(\mathrm{CH}_{3} \mathrm{CH}=\mathrm{CHCHO}\)

Which of the following is true regarding preparation of aldehydes and ketones? (i) Both can be prepared by the oxidation of the concerned alcohol with copper at about \(250^{\circ} \mathrm{C} .\) (ii) Both can be prepared by the oxidation of the concerned alcohol by Oppenauer oxidation. (iii) Both can be prepared by the oxidation of respective alcohol with acidic dichromate. (a) i (b) \(\mathrm{ii}\) and \(\mathrm{iii}\) (c) \(\mathrm{i}\) and iii (d) All the three

Acetal formation is a reversible reaction Under what conditions, the reaction can be forced to proceed only in right (forward) direction? (a) Using excess of alcohol (b) Using high temperature (c) Using dilute acid and excess of alcohol (d) Using dry acid and excess of alcohol

Which of the following statement is false? (a) Cannizzaro reaction is given by aldehydes in presence of alkali (b) Aldol condensation is given by aldehydes in presence of alkali (c) Aldol condensation is given by aldehydes and ketones in presence of acids (d) None of these

Carbonyl compounds, sensitive to both acids as well as bases, can be reduced to hydrocarbons by (a) Clemmensen reduction (b) Wolf-Kishner reduction (c) Thioacetal reduction (d) All of the three

What should be the product when ethylmethyl ketone is treated with peracetic acid (a) Ethyl acetate (b) Methyl propanoate (c) Both (a) and (b) (d) Only acetic acid

When the following three different types of esters are hydrolyzed in a basic medium, the hydroxide anion attacks the acyl carbon in carboxylates while it attacks the alkyl carbon in sulphonates leading to a difference in the site of cleavage. More interestingly, phosphate esters lie somewhat in between carboxylates and sulphonates in that cleavage can occur in either direction. In an acidic solution, all the three types of phosphates (monoalkyl, dialkyl and trialkyl) are hydrolyzed to phosphoric acid, while in a basic solution only trialkyl phosphates undergo hydrolysis and only one alkoxy group is removed. Which of the following factor explains the difference in attack of the nucleophile, \(\mathrm{OH}^{-}\) on carboxylates and sulphonates? (a) Sulphonate anions are weakly basic and hence good leaving groups. (b) Carboxylate anions are strongly basic and hence poor leaving groups. (c) Both (a) and (b) (d) None of the these

Which one does not belong to the same compound? (a) Paraformaldehyde (b) Paraldehyde (c) Trioxane (d) Formalin

Which of the following is not a good reagent in Wittig reaction? (a) \(\mathrm{Ph}_{3} \mathrm{P}=\mathrm{CH}_{2}\) (b) \(\mathrm{Ph}_{3} \stackrel{+}{\mathrm{P}} \overline{\mathrm{C}} \mathrm{HCH}_{2} \mathrm{CH}_{3}\) (c) \(\left(\mathrm{CH}_{3}\right)_{3} \mathrm{CCH}=\mathrm{PPH}_{3}\) (d) \(\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{COCH}=\mathrm{PPh}_{3}\)

When the following three different types of esters are hydrolyzed in a basic medium, the hydroxide anion attacks the acyl carbon in carboxylates while it attacks the alkyl carbon in sulphonates leading to a difference in the site of cleavage. More interestingly, phosphate esters lie somewhat in between carboxylates and sulphonates in that cleavage can occur in either direction. In an acidic solution, all the three types of phosphates (monoalkyl, dialkyl and trialkyl) are hydrolyzed to phosphoric acid, while in a basic solution only trialkyl phosphates undergo hydrolysis and only one alkoxy group is removed. In an aqueous solution, a monoalkylphosphate ester can exist as (a) A neutral ester (b) A monoanion and dianion (c) A monoanion, dianion and protonated ester (d) A monoanion, dianion, protonated ester and neutral ester

Which of the following is not formed in iodoform reaction? (a) \(\mathrm{CH}_{3} \mathrm{COCH}_{2} \mathrm{I}\) (b) \(\mathrm{ICH}_{2} \mathrm{COCH}_{2} \mathrm{I}\) (c) \(\mathrm{CH}_{3} \mathrm{COCHI}_{2}\) (d) \(\mathrm{CH}_{3} \mathrm{COCI}_{3}\)

Grignard reagents \((\mathrm{RMg} X)\) are prepared by the reaction of an organic halide and magnesium metal is in ether solvent. $$\mathrm{R}-\mathrm{X}+\mathrm{Mg} \stackrel{\mathrm{R}-\mathrm{O}-\mathrm{R}}{\longrightarrow} \mathrm{R}-\mathrm{Mg} \mathrm{X}=$$ The solvent (usually diethyl ether or tetrahydrofuran) plays a crucial role in the formation of a Grignard reagent. Alkyl halides are more reactive than aryl and vinyl halides. Indeed, aryl and vinyl chlorides do not form Grignard reagent in diethyl ether. However, an alkyl halide containing an alcoholic -OH group can be converted to Grignard reagent by first protecting the -OH group to tert-butyldimethylsilyl ether which is inert to Grignard reagent. The protecting group is finally liberated by treatment with fluoride ion. Grignard reactions generally occur in dry ether because (a) The stronger acid diethyl ether will displace the weaker \(\mathrm{RH}\) acid from its salt. (b) The stronger acid \(\mathrm{H}_{2} \mathrm{O}\) will displace the weaker acid \(\mathrm{RH}\) from its salt. (c) Water slows down the reaction. (d) Water mixes with ether preventing ether to perform its function.

Grignard reagents \((\mathrm{RMg} X)\) are prepared by the reaction of an organic halide and magnesium metal is in ether solvent. $$\mathrm{R}-\mathrm{X}+\mathrm{Mg} \stackrel{\mathrm{R}-\mathrm{O}-\mathrm{R}}{\longrightarrow} \mathrm{R}-\mathrm{Mg} \mathrm{X}=$$ The solvent (usually diethyl ether or tetrahydrofuran) plays a crucial role in the formation of a Grignard reagent. Alkyl halides are more reactive than aryl and vinyl halides. Indeed, aryl and vinyl chlorides do not form Grignard reagent in diethyl ether. However, an alkyl halide containing an alcoholic -OH group can be converted to Grignard reagent by first protecting the -OH group to tert-butyldimethylsilyl ether which is inert to Grignard reagent. The protecting group is finally liberated by treatment with fluoride ion. \(\mathrm{H}_{2} \mathrm{~N}\left(\mathrm{CH}_{2}\right)_{3} \mathrm{Br}\) cannot be converted into corresponding Grignard reagent because of (a) Reaction between \(-\mathrm{NH}_{2}\) and \(-\mathrm{Br}\) groups present in the same molecule (b) Strong nucleophilic character of the Grignard reagent (c) Strong basic nature of the Grignard reagent (d) All the three factors

Acetyl chloride does not react with (a) Water (b) Sodium acetate (c) 2-methylpropene (d) It reacts with all the three

Grignard reagents \((\mathrm{RMg} X)\) are prepared by the reaction of an organic halide and magnesium metal is in ether solvent. $$\mathrm{R}-\mathrm{X}+\mathrm{Mg} \stackrel{\mathrm{R}-\mathrm{O}-\mathrm{R}}{\longrightarrow} \mathrm{R}-\mathrm{Mg} \mathrm{X}=$$ The solvent (usually diethyl ether or tetrahydrofuran) plays a crucial role in the formation of a Grignard reagent. Alkyl halides are more reactive than aryl and vinyl halides. Indeed, aryl and vinyl chlorides do not form Grignard reagent in diethyl ether. However, an alkyl halide containing an alcoholic -OH group can be converted to Grignard reagent by first protecting the -OH group to tert-butyldimethylsilyl ether which is inert to Grignard reagent. The protecting group is finally liberated by treatment with fluoride ion. The function of tetrahydrofuran in the preparation of Grignard reagent is that it (a) Acts as a solvent (b) Helps in maintaning the reactivity of magnesium (c) Both (a) and (b) (d) None of the these