Ask a Doubt
Request a call back

Join NOW to get access to exclusive study material for best results

CBSE Class 12-science Answered

how is the cabonyl group of aldehyde/ketone affected in the presence of electron donating group like metyl in cyanohydrin reaction?
Asked by prakriti12oct | 14 Feb, 2020, 12:09: PM
answered-by-expert Expert Answer

(a)  Formation of cyanohydrins:

  • On addition of HCN to aldehydes and ketones they yield cyanohydrins.
  • Since the reaction is very slow with pure HCN, it is catalysed with the help of a base and the cyanide ion (CN-) generated as a strong nucleophile adds to carbonyl compounds to give cyanohydrins.
  • The C-O double bond is polarised since oxygen is electronegative than carbon.
  • So the carbonyl carbon is an electrophilic centre and the carbonyl oxygen is a nucleophilic centre.
  • If an electron donating group is present next to carbonyl group then it will slow down the reaction or will retard the rate of reaction.
Answered by Ramandeep | 14 Feb, 2020, 05:57: PM

Concept Videos

Multiple Choice Questions Practice Test
Answered Unanswered My Questions My Answers
CBSE 12-science - Chemistry
C-C=C-CHO ka iupac name
Asked by ukg8612 | 15 Apr, 2024, 07:36: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Chemistry
identify the product when ch3ch=ch-ch2-ch2-c=o-ch3 reacts with following reagents ( a) lialh4/d2o (b) nabh4 (c) c2h5mgbr
Asked by ajayarchi | 08 Feb, 2024, 03:43: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Chemistry
explain the following named reaction aldol condensation
Asked by pallasriramulu9 | 24 Dec, 2023, 06:05: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Chemistry
sir/madam,   1. in NCERT chemistry books in organic chemistry sometimes hydrolysis rxn takes places by acid and water(H2SO4 + H2O/ H3O+/H+ + H2)), base with water(NaOH + H2O/ KOH + H2O) and other times only with water(H2O) what is the difference between the three and when do we use them in rxns ? hydrolysis means breaking or cleavage of compounds using water.... am I right?  2. Is Aldol rxn and condensation only limited to 2 molecules of same aldehyde compound and 2 molecules of same ketone compound? then does it mean that it undergoes self condensation? And cross Aldol rxn and condensation is carried out by two different molecules of aldehydes and two different molecules of ketones. is cross Aldol rxn and condensation also carried out between one aldehyde and one ketone molecules? request u to plz answer all questions
Asked by kaziryan.05 | 30 Jun, 2021, 04:52: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Chemistry
sir/madam, is KMnO4-KOH the chemical formula for alkaline potassium permanganate? like in the NCERT if alkylbenzene is reacted with chromic acid (H2CrO4), will there be any intermediate product just like alkylbenzene when reacted with KMnO4-KOH gives potassium salt of carboxylic acid which then further oxidises to carboxylic acid? also is my formula correct for chromic acid and alkaline potassium permanganate? pls requested to respond to all my questions
question image
Asked by kaziryan.05 | 28 Jun, 2021, 02:34: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Chemistry
IUPAC name 
question image
Asked by amitkumar.cis | 31 Dec, 2020, 10:45: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Chemistry
Conversions from a-g
question image
Asked by shreevarshni1910 | 16 Jun, 2020, 01:36: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Chemistry
how do we convert esters to aldehyd
Asked by yukthas706 | 11 Jun, 2020, 10:00: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Chemistry
how is the cabonyl group of aldehyde/ketone affected in the presence of electron donating group like metyl in cyanohydrin reaction?
Asked by prakriti12oct | 14 Feb, 2020, 12:09: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Chemistry
an organic compound a with molecular formula c6h6o react with zinc dust to give a hydrocarbon B which upon reaction with CH3Cl in the presence of anhydrous AlCl3 gives C.compound C on oxidation with alkaline KMnO4 gives compound D Compound A on further reaction with NH3 in the presence of  anhydrous ZnCl2 gives E identify compound A B C D E and also justify your answer
Asked by Www.keshariramesh32 | 23 Nov, 2019, 02:02: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
My Class Videos Tests ₹ Plans Ask a Doubt
Get Latest Study Material for Academic year 24-25 Click here
×