InterviewSolution
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InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
Write the name of phenyl-substituded groups: a. `C_(6)H_(5) overset(|)(C)Hme`, b `C_(6)H_(5) CH_(2)-` C. `C_(6) H_(5) CH = CH-`, d. `C_(6)H_(5) == CHCH_(2)-` |
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Answer» a. `C_(6) H_(5) overset(beta)(CH_(2)) -` (`beta` Phenethyul) c. Stryl, d. Cinnamyl |
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| 2. |
The decreasing nucleophilic order of the following compounds is: i. `NH_(3)`, ii. `PH_(3)`, iii. `AsH_(3)`, iv. `SbH_(3)`A. `(i) gt (ii) gt (iii) gt (iv)`B. `(iv) gt (iii) gt (ii) gt (i)`C. `(ii) gt (i) gt (iii) gt (iv)`D. `(ii) gt (i) gt (iv) gt (iii)` |
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Answer» Correct Answer - `b` Since nucleophilic centre is different ad belongs to the same group so basic character and nuclophilicity are reversed. `SbH_(3) gt AsH_(3) gt Ph_(3) gt NH_(3)` |
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| 3. |
The halogen which is most reactions , in the halogenation of alkanes under sunlight is ......... |
| Answer» Correct Answer - Flourine | |
| 4. |
Nitration of xylene gives only one mono-nitro derivaties. Which xylene is it?A. orhtoB. metaC. paraD. Both `o` and `p` |
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Answer» Correct Answer - `c` `p-` Isomer gives only one product on `SE` reaction `(OMP = 231)`. |
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| 5. |
Among the following in which cases is the `o//p` ratio on nitration more the first compound? |
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Answer» (c,d) In (a) and (c) in the nitration of `alkyl` benzene, the `o//p` ratio is the order `Me (1.58) gt Et (0.94) gt Me_(2)CH-(0.49) gt Me_(2)C (0.22)`. This is largly due to the steric effect of the alkyl group and `overline(e)` donation by hyperconjugation. So, the reactivity order is: `PhCH_(3) gt PhEt gt PhCHMe_(2) gt PhCMe_(3)`. So, in (b) adn `o//p` ratio is: `(II) gt (i)`. In (c), the `o//p` ratio is: `(I) gt (II)`. So, in (b) and (d), for nitraction of halogen substituent, the reactivity oder is: `I gt Br gt Cl gt F` (due to combined effect of `-1` and `+R`). So, in (b), `o/p` ratio is: `(II) gt (I)` So in `(d), o//p` ratio is (I) gt (II)` |
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| 6. |
Which is least reactive towards nucleophilic substitution `(S_(N^(2)))`A. B. `Me_(3)C - Cl`C. `PhCl`D. `MeCH(Cl)Me` |
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Answer» Correct Answer - `c` Aryl halides are least reactive due to resonance. |
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| 7. |
Both `t-`butyl and `(-SO_(3)H)` groups are used as a blocking group in certain synthesis of organic compounds. Which of the following statements are correct?A. `t-` Butyl group is easily introduced by any of the varitions of the Friedel-Crafts alkylation reacton.B. t-` Butyl group can be intorduced by using: I. `Me_(3)C - Cl + AlCl_(3)` II. `Me_(3)C - OH + BF_(3)` III. C. `t-` Butyl group can be easily removed under acidic conditions, beucase of the stability of tert-butyl cations.D. `t-` Butyl group has advantage over a `(-SO_(3)H)` group as a blocking group, becuase `t-` butyl group activates the ring to further `SE` reaction. |
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Answer» Correct Answer - `(a,b,c,d)` `(a,b,c,d)` All statements are self-explantory. |
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| 8. |
Which are the sources of phenol?A. CumeneB. Hydrolysi of benzene diaxonium saltC. Middle oil of coal tar distilationD. Reaction of diazonium salt with `H_(3)PO_(2)` |
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Answer» Correct Answer - `(a,b,c)` Statements `a,b` and `c` are correct but (d) is wrong becuae reaction (d) gives benzene. |
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| 9. |
Predicrt the order of reactivity of the following compounds in `SN^(1)` and `SN^(2)` reactions. |
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Answer» First compound is a secoundary halide and the other three are tertiary halides. Also, the reactivity follows the order chloride lt bromide lt iodie. Thuys the compounds as given are arranged in the decreasing order of reactivity in `SN^(1)` and `SN^(2)` reactions. `SN^(1) implies (IV) gt (III) gt (II) gt (I)` `SN^(2) implies (I) gt (IV) gt (III) gt (II)` |
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| 10. |
`(A) would be:A. B. C. D. |
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Answer» Correct Answer - `a` `SE` reaction takes place in central ring because it is attached to `overline(e)` donating (by resonance) (activating) two `Ph-`rings. Moreover in `NO_(2)^(o+) ClO_(4)^(o-), NO_(2)^(o+)` is an electrophile. |
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| 11. |
Which will react faster with `NBS`?A. `C_(6)H_(6)`B. `CH_(4)`C. TolueneD. Cyclorpropane |
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Answer» Correct Answer - `c` Toluene has an allyic group. |
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| 12. |
Which of the following syntheses could not be doen without involving blocking positions on the ring?A. B. C. D. |
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Answer» Correct Answer - `c` In (c), phenol is `o-` and `p-` directing so both the products would be obtained. Thus to obtain ortho-product exclusively, `p-` position has to be blocked first, and then `Br` intoduced in ortho-postion, followed by the removel of group from `p-` postion. |
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| 13. |
Give the decreasing order of `(o+p)/(m)` ratio of the reactions or decreasing order of the reactivity given is problem `11.11`. |
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Answer» Reactivity order of `SE` reactiion or `((o+p)/(m))` ratio (same explanation as in Problem `11.10`) `o-, p-` directing reactivity and `((o+p)/(m))` ratio order. i. `underset((VIII))(-NH-)overset(O)overset(||)(C-) underset(gt)(gt) underset((I))(-R) (-CHMe_(2) underset(gt)(gt) underset((II))(-CMe_(3))) underset(gt)(gt) underset((VII))(-Ar) underset(gt)(gt) underset((III))(I)` ii. `m-` directing reactivity order: `underset((V))(-CX_(3)) underset(gt)(gt) underset((VI))(-C) -= N underset(gt)(gt) underset((IV)) overset(O)overset(||)(-C-O-R)` But `((o+p)/(m))` ratio order of compounds in Problem 11.11 is: `underset((VIII))(O) underset(gt)(gt) underset((I))(A) underset(gt)(gt) underset((II))(C) underset(gt)(gt) underset((VII))(M) underset(gt)(gt) underset((III))(E) underset(gt)(gt) underset((IV))(G) underset(gt)(gt) underset((VI))(K) underset(gt)(gt) underset((V))(I)` |
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| 14. |
Which of following is most easily cleaved by `HBr`.A. B. C. D. |
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Answer» Correct Answer - `a` More strained the ring, more easilty it is cleaved. Three membered ring is highly strained. |
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| 15. |
In which case will `SE` not be in `m-` position?A. B. C. D. |
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Answer» Correct Answer - `a` a. `(-overset(O)overset(||)(C)-)` group, b. (-overset(o+)(N) Me_(3))` group c. It is weakly deactivating btu `o, p-` director. d. `(-CF_(3))` group, `(a),(b)` and `(d) are `m-` director. |
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| 16. |
Give the decreasing order of `((o + p)/(m))` ratio for the nitration of compounds in Problem `11.9`. |
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Answer» Greater the reactivity of `o,p-` directing substiuent, more is the `(( o + p)/(m))` ratio. Similarly, greater the reativity of `m-` directing substituent, less is the `(( o + p)/(m))` ratio. IN problem `11.9`, the reactivity order of `o-,p` directing substituent and of `m-` directing substituent is: `o-,p-` Directing reactivity and `(( o + p)/(m))` ratio order: `underset((IV))(-OR) underset(gt)(gt) underset((I))(-OCOR) underset(gt)(gt) underset((VII))(-CH=CH-COOH) underset(gt)(gt) underset((II))(-CH=CH-NO_(2)) underset(gt)(gt) underset((V))(-R)` m-` directing reactivity order: `underset((VI)) overset(O) overset(||) (-C) -R underset(gt)(gt) underset((III))overset(O)overset(||)(C) - NH_(2)` `(o+p)/(m)` ratio: `(III) gt (IV)` Hence `((o + p)/(m))` ratio order is: `(IV) gt (I) gt (VII) gt (II) gt (V) gt (III) gt (VI)` |
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| 17. |
Which is most reactive towards `Br_(2)` in the prsence of `FeBr_(3)`?A. AnisoleB. BenzeneC. BromolbenzeneD. Nitrobenzene |
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Answer» Correct Answer - `a` More the `EDG`, more reactive is the `SE` In anisole, `(-underset(..)overset(..)(O)CH_(3))` is `overline(e)` donating by resonance `SE` order: `(a) gt (b) gt (c) gt (d)`. |
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| 18. |
. The product (B) isA. B. C. D. |
| Answer» Correct Answer - B | |
| 19. |
. The major product (A) isA. B. C. D. |
| Answer» Correct Answer - D | |
| 20. |
`C_(6)H_(5)NH_(2) overset(NaNO_(2)+HCl)underset(0-5^(@)C) X overset(H_(2)O)underset(Delta)toY,` the product is :A. Benzenediazonium chlorideB. NitrobenzeneC. PhenolD. Cresol |
| Answer» Correct Answer - C | |
| 21. |
The decreasing order of reactivity of `m-`nitrobromobenzene (I0, 2, 4, 6-trinitrobromo-benzene (II), `p-`nitrobromobenzene (III), and 2,4-dinitrobromobenzene (IV), towards `OH^(-)` ions is:A. `I gt II gt III gt IV`B. `II gt IV gt III gt I`C. `IV gt II gt III gt I`D. `II gt IV gt I gt III` |
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Answer» Correct Answer - B More `-NO_(2)` group more will be reactivity towards `HO^(Θ)` ion towards `S_(N)Ar`. |
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| 22. |
The decreasing basic order of the following compounds is: i. `H_(2)O`, ii. `H_(2)S`, iii. `H_(2)Se`, iv. `H_(2)Te`A. `(i) gt (ii) gt (iii) gt (iv)`B. `(iv) gt (iii) gt (ii) gt (i)`C. `(iiii) gt (i) gt (ii) gt (iv)`D. `(iv) gt (ii) gt (i) gt (iii)` |
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Answer» Correct Answer - `a` The basic character fo hydrides of 16 group decreases down the group. Size increases down the group and `LP overline(e)` density decreases. Basic: `H_(2)O gt H_(2)S gt H_(2)Se gt H_(2)Te` |
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| 23. |
The decresing nuclephilic order of the following is: i. `F_(3)CSO_(3)^(o-)`, ii. `Cl_(3)C-COO^(o-)` iii. `PhSO_(3)^(o-)`, iv. `MeSO_(3)^(o-)`A. `(i) gt (ii) gt (iii) gt (iv)`B. `(iv) gt (iii) gt (ii) gt (i)`C. `(ii) gt (iv) gt (iii) gt (i)`D. `(iv) gt (ii) gt (i) gt (iii)` |
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Answer» Correct Answer - `c` Same nucleophilc centre, basically and nucelphilicity are same: Nucleophilicity: `Cl_(3)CCOO^(o-) gt MeSO_(3)^(o-) gt PhSO_(3)^(o-) gt F_(3)CSO_(3_^(o-)` |
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| 24. |
The decreasing leaving group order of the following is: i. `F_(3)CSO_(3)^(o-)`, ii. `Cl_(3)C-COO^(o-)` iii. `PhSO_(3)^(o-)`, iv. `MeSO_(3)^(o-)`A. `(i) gt (ii) gt (iii) gt (iv)`B. `(iv) gt (iii) gt (ii) gt (i)`C. `(iiii) gt (i) gt (ii) gt (iv)`D. `(i) gt (iii) gt (ii) gt (i)` |
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Answer» Correct Answer - `d` Nucelphilicity and leaving group are reversed. Fugavity: `(i) gt (iii) gt (Iv) gt (ii)` |
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| 25. |
The decreasing nucleophilic order of the following compounds is: i. `PhSO_(3)^(o-)`, ii. `C_(2)H_(5)SO_(3)^(o-)`, iii. `C_(2)H_(5)COO^(o-)`, iv. `overset(o-)(C)N`, v. `overset(o-)(O)H`A. `(v) gt (iv) gt (iii) gt (ii) gt (i)`B. `(i) gt (ii) gt (iii) gt (iv) gt (v)`C. `(iv) gt (v) gt (iii) gt (ii) gt (i)`D. `(i) gt (ii) gt (iii) gt (v) gt (iv)` |
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Answer» Correct Answer - `a` Nucelphilic centre on `overset(o-)(C)N` is different from others, but belongs to the same period. Basic and nucelophilic orders are same. |
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| 26. |
The decreasing fugacity order of the following compounds is: i. `PhSO_(3)^(o-)`, ii. `C_(2)H_(5)SO_(3)^(o-)`, iii. `C_(2)H_(5)COO^(o-)`, iv. `overset(o-)(C)N`, v. `overset(o-)(O)H`A. `(v) gt (iv) gt (iii) gt (ii) gt (i)`B. `(i) gt (ii) gt (iii) gt (iv) gt (v)`C. `(iv) gt (v) gt (iii) gt (ii) gt (i)`D. `(i) gt (ii) gt (iii) gt (v) gt (iv)` |
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Answer» Correct Answer - `b` Fugacity and basic orders are reversed. `(i) gt (ii) gt (iii) gt (iv) gt (v)` |
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| 27. |
The decreasing nucelophilic order of the following compounds is: i. overset(o-)(C)H_(3)`, ii. Overset(o-)(O)H`, iii. `CH_(3)COO^(o-)`, iv. `H_(2)O`A. `(i) gt (ii) gt (iii) gt (iv)`B. `(iv) gt (iii) gt (ii) gt (i)`C. `(iiii) gt (i) gt (ii) gt (iv)`D. `(iii) gt (ii) gt (iv) gt (i)` |
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Answer» Correct Answer - `a` Compared to the others, `overset(io-)(C)H_(3)` has different nuclophillic centre, however it belongs to the same period. Basically and nucelophilicity order the same. `overset(o-)(C)H_(3) gt overset(o-)(O)H gt CH_(3)COO^(o-) gt H_(2)O` |
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| 28. |
Give the decreaes order of`ArSN`reaction of the following with`NaOMe`: |
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Answer» a(II)gt(IV)gt(III)gt(I). The leaving group `F` is same,so the`ArSN` reactivity is determined y`EWF(-NO_(2))`group.More the `EWF`,more rapid is the reaction.`EW`power of `(-NO_(2)`at`ogtpgtm`.Although negative charge in arenanion is equally stabilised by `(-NO_(2)`grouo at`o-`and `p-position,-Ipower of (-NO_(2)`group si slighly more at ortho than at para. (IV)gt(III)gt(II)gt(I) More the number of `EWF(-NO_(2))`,faster is the `ArSN`reaction (c ) (I)gt(II)gt(III)gt(IV` The leaving groups are differently .More the`EN`of the leaving group,more is the negative charge srtabilised in the intemediate arenanion,and hence faster is the reaction. (d)`(II)gt(I)gt(III)gt(IV)` The leaving group`Cl`is same.`ArSN`reactivity is determined by`EWG`,More the`EW`power,more is the reactivity .The `EW` power of `-NO_(2)gt-SO_(3)Hgt-C-=Ngt-CHO`. |
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| 29. |
Arrange the following in increasing order of reactivity towards sulphonation with fuming sulphuric acid. Benzene, toluene, methoxy benzene, chlorobenzene. |
| Answer» Chorobenzene lt Benzene lt Toluene lt Methoxy benzene. | |
| 30. |
Which of the folliwng compounds is the most reactive towards electrophilic substitution reaction?A. B. C. D. |
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Answer» Correct Answer - `a` It is more reactive towards `SE` reactiions, due to hyperconjugation. |
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| 31. |
Which of the folliwng is the correct order of the order of the rate of reaction of `C_(6)H_(6), C_(6)D_(6)` and `C_(6) T_(6)` towards nitration?A. `C_(6) H_(6) gt C_(6) D_(6) gt C_(6) T_(6)`B. `C_(6) H_(6) = C_(6) D_(6) = C_(6) T_(6)`C. `C_(6) H_(6) gt C_(6) D_(6) = C_(6) T_(6)`D. `C_(6)T_(6) gt C_(6) D_(6) gt C_(6) H_(6)` |
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Answer» Correct Answer - `b` Sulphonation is a reversable process and shows `1^(@)` kinetic isotope effect, wheras other `SE` reactiosn (i.e. nitration halogation, etc.) do not show `1^(@)` kinetic isotope effect. |
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| 32. |
Which of the folliwng is the order of the rate of reaction of `C_(6)H_(6),C_(6)D_(6)`, and `C_(6)T_(6)` towards sulphonation?A. Same rates of reactions of `C_(6)D_(6), C_(6)D_(6)` and `C_(6)T_(6)`.B. `C_(6)T_(6) gt C_(6) D_(6) gt C_(6) H_(6)`C. `C_(6) H_(6) gt C_(6) D_(6) gt C_(6) T_(6)`D. `C_(6) H_(6) gt C_(6) D_(6) = C_(6) T_(6)` |
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Answer» Correct Answer - `c` Sulphonation is a reversable process and shows `1^(@)` kinetic isotope effect, wheras other `SE` reactiosn (i.e. nitration halogation, etc.) do not show `1^(@)` kinetic isotope effect. |
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| 33. |
The reaction conditions leading to the best yield of `C_(2)H_(5)Cl` areA. `C_(2) H_(6) ("Excess") + Cl_(2) overset(U. V. "light")(rarr)`B. `C_(2) H_(6) + Cl_(2) ("Excess") underset("room temp.")overset("Dark")(rarr)`C. `C_(2) H_(6) + Cl_(2) ("Excess") overset(U.V."light")(rarr)`D. `C_(2) H_(6) + Cl_(2) overset(U.V."light")(rarr)` |
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Answer» Correct Answer - `a` `C_(2) H_(6) ("Excess") + Cl_(2) overset(U.V. "light")(rarr) C_(2)H_(5)Cl + HCl` |
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| 34. |
`C_(2)H_(5)I overset(AgNO_(2))rarr underset(("major product"))("X. Here X")` is :A. `C_(2)H_(5) - overset(O)overset(||)(N) rarr O`B. `C_(2)H_(5) - O - N = O`C. `C_(2) H_(5) - N = O`D. All of above |
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Answer» Correct Answer - `c` `RX` with `AgNO_(2)` gives nitroalkane. |
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| 35. |
For the preparation of chloroethane,A. `HCl` gas is passed through ethanol.B. Ethanol is treated with thionyl chloride in the presence of dimethyl amine or pyride.C. Ethyl sulphide is treated with hydrogen chloride.D. Any of the above methods can be empolyed. |
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Answer» Correct Answer - `b` `C_(2) H_(5) OH overset(SOCl_(2))(rarr) C_(2)H_(5)Cl + SO_(2) + HCl` a. `HCl` bond is strong, no reaction. |
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| 36. |
`underset("Specific rotation" = +50^(@))(Ph-CH(OH)CH_(3)) overset(SOCl_(2))(rarr) underset(Cl)underset(|)(PhCH) - CH_(3)` What si the specific rotation of the product?A. `+50^(@)`B. `+60^(@)`C. `-60^(@)`D. Zero |
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Answer» Correct Answer - `b` It is an example of `SN^(1)` reaction in which retention takes place. So, if reactant specific rotation is positive, it should be positive for the product also, but of different value since the reactant and product are different. |
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| 37. |
Give the order of reactivityh towards `SN^(1)` reaction of the following: i. `ClCH_(2)CH = CH_(2)` ii. `CH_(3)CH_(2)CH_(2)Cl` iii. `CH_(3)CH = CHCl` |
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Answer» `(i) gt (ii) gt (iii)`. The reacticity of `SN^(1)` depends on the stabillity of the carbocation being formed. Allylic cation gt `1^(@)` cation gt Vinylic cation. |
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| 38. |
`CH_(3)Br +Nu^(Theta) rarr CH_(3)-Nu +Br^(Theta)` The decreasing order of the rate of the above reaction with nucleophiles `Nu^(Theta) A` to `D` is- `[Nbar(u) =(A) phO^(-), (B) AcO^(-), (C)H bar(O),(D) CH_(3)bar(O)]`A. `(D) gt (C) gt (A) gt (B)`B. `(D) gt (C) gt (B) gt (A)`C. `(C) gt (D) gt (A) gt (B)`D. `(B) gt (D) gt (C) gt (A)` |
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Answer» Correct Answer - `c` Acidic character: `underset(pK_(a) "value:")() underset(4.75)(ACOH) gt underset(9.9)(PhOH) gt underset(15.5)(MeOH) gt underset(15.74)(H_(2)O)` Basic and nucelphilic characters are same because of same nucleophilic centre. Nucleophliic order: `{:(AcO^(Theta),lt,PhO^(Theta),lt,MeO^(Theta),lt,overset(Theta)(O)H),((B),lt,(A),lt,(D),lt,(C)):}` |
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| 39. |
Hofmann rearrangement In the Hofmann rearrangement an unsubstitued amide is treated with sodium hydroxide and bromine to give a primary amine that has one carbon lesser than starting amide. Gneral reaction: If the migrating group is chiral then its configuration is retained. Electron releasing effects in the migrating group increase reactivity of Hofmann rearangement. Which of the following compound(s) cannot give Hoffman rearrangement:A. B. `CH_(3)-CH_(2)-overset(O)overset(||)(C )-NH-Ph`C. D. `Ph-overset(O)overset(||)(C )-NH_(2)` |
| Answer» Correct Answer - B | |
| 40. |
The experimentakkt determind rate equiaction for the alkaline hydeolysis of `RBr` is given by: Rate `= K [RBr] [overset(theta)(O)H]` Which of the following staements is inconsists with these observations?A. The reaction is first order with respect to `RBr`B. The reaction is seound order overallC. The reaction process is false.D. The rate-determining step is bimolecular. |
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Answer» Correct Answer - `c` The reaction is wrong because alkaline hydrolysis of `RX` does not take place. |
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| 41. |
Reimer-Tiemann reaction introduces an aldehyde group on to the aromatic ring of phenol, ortho to the hydroxyl group. This reacrtion involves electrophilic aromatic subsititution. It is a general method for the synthesis of subsituted salicyladehydes as depiced below: Which one of the following reagents is used in the above reaction ?A. aq. `NaOH + CH_(3)Cl`B. aq. `NaOH + CH_(2)Cl_(2)`C. aq. `NaOH + CHCl_(3)`D. aq. `NaOH + C Cl_(4)` |
| Answer» Correct Answer - C | |
| 42. |
Reimer-Tiemann reaction introduces an aldehyde group on to the aromatic ring of phenol, ortho to the hydroxyl group. This reacrtion involves electrophilic aromatic subsititution. It is a general method for the synthesis of subsituted salicyladehydes as depiced below: The electrophile in this reaction is:A. `:CHCl`B. `.^(+)CHCl_(2)`C. `:CCl_(2)`D. `.^(.)CCl_(3)` |
| Answer» Correct Answer - C | |
| 43. |
Hofmann rearrangement In the Hofmann rearrangement an unsubstitued amide is treated with sodium hydroxide and bromine to give a primary amine that has one carbon lesser than starting amide. Gneral reaction: If the migrating group is chiral then its configuration is retained. Electron releasing effects in the migrating group increase reactivity of Hofmann rearangement. Arrange the following amides according to their relative reactivity when reacted with `Br_(2)` in excess of strong base: A. `IV gt I gt II gt III`B. `II gt I gt III gt IV`C. `II gt IV gt III gt I`D. `II gt I gt IV gt III` |
| Answer» Correct Answer - D | |
| 44. |
n-propylamine containing no secondary and tertiary amines as impurities is prepared byA. Hoffman synthesisB. Gabriel synthesisC.D. reacting n-propylchloride and ammonia |
| Answer» Correct Answer - B | |
| 45. |
n-propylamine containing no secondary and tertiary amines as impurities is prepared byA. Hoffmann synthesisB. Gabriel synthesisC. reacting n-propylchloride with ammoniaD. none of these |
| Answer» Correct Answer - B | |
| 46. |
In order to prepare a `1^(@)` amine from an alkyl halide with simultaneous addition of one `CH_(2)` group in the carbon chain, the reagent used as source of nitrogen is…..A. Sodium amide `NaNH_(2)`B. Sodium azide, `NaN_(3)`C. Potassium phthalimide, KCND. Potassium phthalimide, `C_(6)H_(4)(CO)_(2)N^(-)K^(+)` |
| Answer» Correct Answer - C | |
| 47. |
Fluorination of an aromatic ring is easily accompolished by treating a diazonium salt with `HBF_4`. Which of the following conditions is correct about this reaction ?A. Only heatB. `NaNO_(2)//Cu`C. `Cu_(2)O //H_(2)O`D. `NaF//Cu` |
| Answer» Correct Answer - A | |
| 48. |
Reimer-Tiemann reaction introduces an aldehyde group on to the aromatic ring of phenol, ortho to the hydroxyl group. This reacrtion involves electrophilic aromatic subsititution. It is a general method for the synthesis of subsituted salicyladehydes as depiced below: The structure of the intremediate (I) is:A. B. C. D. |
| Answer» Correct Answer - B | |
| 49. |
Hofmann rearrangement In the Hofmann rearrangement an unsubstituted amide is treated with sodium hydroxide and bromide to give a primary amine that has one carbon lesser than starting amide. In the migrating group is chiral then is configuration is retained. Electron releasing effects in the migrating group increases reactivity of Hofmann rearrangement. Which of the following compounds (s) cannot give Hofmann rearrangement :B. `CH_(3)-CH_(2)-overset(O)overset(||)(C)-NH-Ph`D. `Ph-overset(O)overset(||)(C)-NH_(2)` |
| Answer» Correct Answer - B | |
| 50. |
Give 3 methods to distinguish primary amine from secondary and tertiary. |
| Answer» Correct Answer - (i) Isocyanide test (ii) Hinsberg test (iii) `NaNO_(2)+HCl` test | |