Mechanism Of Nucleophilic Acyl Substitution Of The Acyl Derivative

The mechanism of nucleophilic acyl substitution in the acyl derivative proceedds as follows which among the following is false?

Reaction Mechanism : nucleophilic substitution-sn2

Reaction Mechanism : nucleophilic substitution,1)components OF nucleophilic substitution,nucleophile,Sn1 reactions

Reaction Mechanism : nucleophilic substitution,1)components OF nucleophilic substitution,a)substrale,b)Leaving groups,c)solvent theory

Give the decreasing order of reactivity of the following towards hydrolysis (or nucleophilic acyl substitution) : (i) (I) PhCOOMe (II) (II) (IV) (ii) (I) PhCOCl (II) (iii) (I) PhCOCl (III) Me_2 CHCOCl (IV) Me_3 C-COCl . (b) Give the decreasing order of transacylation reactivities and nucleophilic acyl substitution reactivities fo the following : (I) MeCOCl (II) MeCON_3 (III) (MeCO)_2 O (IV) MeCOOMe (V) MeCONH_2 .

Acyl nucleophilic substitution (SNAC) (SNAE)

Arrange the following in the decreasing order of nucleophilic acyl substitution reaction. .

Amides undergo hydrolysis to yield carboxylic acid plus amine on heating in either aqueous acid or aqueous base. The conditions required for amide hydrolysis are more severe than those required for the hydrolysis of esters, anhydrides or acid chlorides, but the mechanism is similar (nucleophilic acyl substitution). Nucleophilic acyl substitutions involve a tetrahedral intermediate, hence these are quite different from alkyl substitution (RCH_(2)Broverset(NaCN)to RCH_(2)CN) which involves a pentavalent intermediate or transition state. One of the important reactions of esters is their reaction with two equivalent of Grignard reagent to give tertiary alcohols. Which of the following constitutes the best substrate during the acidic hydrolysis of amides?

Both carbonyl compounds and acid derivatives though they contain grouping yet the reactions given by them are entirely different. As Aldehydes and Ketones give addition product with a nucleophile, while carboxylic acid derivatives give nucleophilic acyl substitution through addition/elimination mechanism. Where X- = -Cl - O-overset(O)overset(||)C-R-OR, -NR(R) etc. Why aldeydes and Ketones give nucleophilic addition reaction while acid derivatives prefer nucleophilic acyl substititution reaction?