When semicarbazide reacts with a ketone (or aldehyde) to form semicarbazone. Only one nitrogen atom of semicarbazide acts as a nucleophile and attack the carbonyl carbon of the ketone. The product fo the reaction consequently is `R_(2)C=N- NH-CONH_(2)` rather than `R_(2)C=NCONH-NH_2`. what factor account for the fact that two nitrogen atoms of semicarbazide are relatively non nucleophilic ?

When semicarbazide reacts with a ketone (or aldehyde) to form semicarb

1.	When semicarbazide reacts with a ketone (or aldehyde) to form semicarbazone. Only one nitrogen atom of semicarbazide acts as a nucleophile and attack the carbonyl carbon of the ketone. The product fo the reaction consequently is `R_(2)C=N- NH-CONH_(2)` rather than `R_(2)C=NCONH-NH_2`. what factor account for the fact that two nitrogen atoms of semicarbazide are relatively non nucleophilic ?
Answer» Correct Answer - Two nitrogen atoms of semicarbazide that are adjacent to the (C=O) group have their lone pair present in conjuction so nucleophilicity decreases.

Discussion

No Comment Found

Related InterviewSolutions

A and B respectively areA. `H_(2)//Pt,LiAlh_(4)//H_(2)O`B. `H_(2)//Pt,H_(2)//Pt`C. `LiAlH_(4)//H_(2)O,LiAlH_(4)//H_(2)O`D. `LiAlH_(4)//H_(2)O,H_(2)//Pt`
In the gives reaction sequence `CH_(3)CH_(2)underset(O)underset(||)C CH_(2)CH_(3)overset(Br_(2)//CH_(3)COOH)rightarrow Xoverset(Br_(2)//NaOH)rightarrow Y` X,Y respectively areA. `CH_(3)CH_(2)COCHBrCH_(3)&CH_(3)CH_(2)COCBr_(2)CH_(3)`B. `CH_(3)CH_(2)COCBr_(2)CH_(3)&CH_(3)CH_(2)COCBrCH_(3)`C. `CH_(3)CH_(2)COCBr_(2)CH_(3)&CH_(3)CH_(2)COCBr_(2)CH_(3)`D. `CH_(3)CH_(2)COCHBr_(2)CH_(3)&CH_(3)CH_(2)COCHBr_(2)CH_(3)`
A+B`overset(dilOH^(-))rightarrow Ph -CH =CH-underset(CH_(3))underset(|)C=O` identfy A&B in the above reactionA. Acetophenone, AcetoneB. Acetophenone, AcetaldehydeC. Acetone ,BenzaldehydeD. Acetaldehyde, Benzoic acid
The possible number of steroisomers of the product of following reaction would be: `Ph-Ch=CH-underset(CH_(3))underset(|)CH-underset(H)underset(|)C=Ounderset(pH=4.5)overset(h_(2)N-OH)rarr+`A. 2B. 6C. 8D. 4
The major product H in the given reaction sequence is `CH_(3)-CH_(2)-CO-CH_(3) overset(._(Theta)CN)toG overset(95% H_(2)SO_(4)) underset("Heat")toH`A. `CH_(3)-CH=underset(CH_(3))underset(|)(C)-COOH`B. `CH_(3)-CH=underset(CH_(3))underset(|)(C)-CN`C. `CH_(3)-CH_(2)-overset(OH)overset(|)underset(CH_(3))underset(|)(C)-COOH`D. `CH_(3)-CH=underset(CH_(3))underset(|)(C)-CO-NH_(2)`
`Ch_(3)-overset(O)overset(||)C-overset(O)overset(||)C-Phoverset(CH_(3)CO_(3)H)rarr` product, Product will be :A. `CH_(3)-O-overset(O)overset(||)C-overset(O)overset(||)C-Ph`B. `CH_(3)-overset(O)overset(||)C-overset(O)overset(||)C-O-Ph`C. `CH_(3)-overset(O)overset(||)C-O-overset(O)overset(||)C-Ph`D. `Ph-overset(O)overset(||)C-O-overset(O)overset(||)C-CH_(2)OH`
`E overset(CF_(3)CO_(3)H)rarr` Product :A. B. C. D. None of these
The additon reaction of enol or enolate to the carbonyl function of aldehyde or ketone is known as aldol addition . The `beta`-hydroxyaldehyde or `beta-`hydroxyketone so obtained undergo dehydration in second step to produce a conjugated enone. The first part of reaction is an addition reaction and the second part is an elimination reaction. Carbonyl compound having `alpha`-hydrogen undergoes aldol condensation reaction . `2CH_(3)CH_(2)-overset(O)overset(||)C-Hunderset(Delta)overset(""^(Ө)OH)rarrCH_(3)CH_(2)CH=underset(CH_(3))underset(|)C-overset(O)overset(||)C-H` Find out product of following reaction : X is :A. `CH_(3)-CH=CH-overset(O)overset(||)C-Ph`B. C. `Ph-overset(O)overset(||)C-CH=underset(Ph)underset(|)C-CH_(3)`D. None of these
The additon reaction of enol or enolate to the carbonyl function of aldehyde or ketone is known as aldol addition . The `beta`-hydroxyaldehyde or `beta-`hydroxyketone so obtained undergo dehydration in second step to produce a conjugated enone. The first part of reaction is an addition reaction and the second part is an elimination reaction. Carbonyl compound having `alpha`-hydrogen undergoes aldol condensation reaction . `2CH_(3)CH_(2)-overset(O)overset(||)C-Hunderset(Delta)overset(""^(Ө)OH)rarrCH_(3)CH_(2)CH=underset(CH_(3))underset(|)C-overset(O)overset(||)C-H` Find out major product of following reaction : A. B. C.
The additon reaction of enol or enolate to the carbonyl function of aldehyde or ketone is known as aldol addition . The `beta`-hydroxyaldehyde or `beta-`hydroxyketone so obtained undergo dehydration in second step to produce a conjugated enone. The first part of reaction is an addition reaction and the second part is an elimination reaction. Carbonyl compound having `alpha`-hydrogen undergoes aldol condensation reaction . `2CH_(3)CH_(2)-overset(O)overset(||)C-Hunderset(Delta)overset(""^(Ө)OH)rarrCH_(3)CH_(2)CH=underset(CH_(3))underset(|)C-overset(O)overset(||)C-H` Which of the following will give aldol condensation ?A. B. `H-overset(O)overset(||)(C)-H`C. D.

Discussion

No Comment Found

Related InterviewSolutions

Reply to Comment