by Corene Spencer
Published 3 years ago
Updated 2 years ago
Imines are reactive due to their ability to act as electron 'sinks'. The nitrogen of the C=N bond is readily protonated, yielding a protonated imine. This serves as an electron-accepting group, which, when present in an adduct, can pull electrons away from the bonds in the attached molecule.Oct 30, 2018
Which is more stable amine or imine?
Imine is more stable than enamine.
Which is the most stable imine?
The cyclohexane-1,3,5-triimine tautomer is benzene-1,3,5-triamine, which is aromatic. This makes this trienamine form much more stable than any of the other possible tautomeric forms.
Are imines more reactive than ketones?
Imines are less electrophilic than aldehydes and ketones The decreased electrophilicity of imines is readily accounted for by the lower electronegativity of nitrogen compared with that of oxygen.
Do imines react with water?
Description: Treatment of imines with water leads to their hydrolysis back to aldehydes (or ketones) and an amine. Notes: The reaction is assisted through the use of an acid catalyst.
Are imines unstable?
Imines are reactive due to their ability to act as electron 'sinks'. The nitrogen of the C=N bond is readily protonated, yielding a protonated imine. This serves as an electron-accepting group, which, when present in an adduct, can pull electrons away from the bonds in the attached molecule.
How do you stabilize imine?
14.9. Simple imines are usually generated in situ, although imines can be stabilized by the presence of electron-withdrawing groups on the nitrogen.
Are imines stable?
Imine group stable at high Temp. however in presence of moisture it undergoes hydrolysis.
Why imines are more stable than enamines?
because the latter one contains a carbon- nitrogen double bond which is very stable. So, imine is more stable than enamine form.
How do imines react?
Imines are widely used as intermediates in the synthesis of heterocycles. Aromatic imines react with an enol ether to a quinoline in the Povarov reaction. Imines react, thermally, with ketenes in [2+2] cycloadditions to form β-lactams in the Staudinger synthesis. Several variants have been described.
Does imine formation require acid?
Imines are formed when any primary amine reacts with an aldehyde or ketone under appropriate conditions. Imine formation requires an acid catalyst, otherwise the reaction is very slow. The acid is needed for the elimination of water.
Is imine group electron withdrawing?
Introduction. Imines may be employed as dienophiles in hetero-Diels-Alder reactions. These reactions involve the lowest unoccupied molecular orbital (LUMO) of the imine, meaning that imines substituted with electron-withdrawing groups on nitrogen are the most reactive.
Why is the imine brightly colored?
A1) Most organic compounds are not brightly colored, but the imine formed in this reaction is a chromophore with a bright orange. Color in imines and other organic chromophores can arise from an absorption of a photon to promote an electron from a π to π* orbital or a lone pair (n) to π* orbital.
Are imines stable?
Imine group stable at high Temp. however in presence of moisture it undergoes hydrolysis.
What is an imine functional group?
An imine is a functional group or chemical compound containing a carbon–nitrogen double bond. Imines are chemical molecules with a double bond between carbon and nitrogen (C=N). They are made by substituting the oxygen atom in aldehydes and ketones with the (N-R) group. Imines are compounds with a C=N double bond.
34 hours ago
Are imines unstable? Imine Formation One of the two shared pairs of electrons that constitute the double bond between C and O is transferred to O. ... This forms the characteristic C=N double bond, and the oxygen is concurrently eliminated as water. The loss of the hydroxyl group is difficult, as the resultant hydroxyl ion is unstable.
26 hours ago
Are imines unstable? Imine Formation One of the two shared pairs of electrons that constitute the double bond between C and O is transferred to O. ... This forms the characteristic C=N double bond, and the oxygen is concurrently eliminated as water. The loss of the hydroxyl group is difficult, as the resultant hydroxyl ion is unstable.
19 hours ago
Imine are oxidized with meta-chloroperoxybenzoic acid (mCPBA) to give an oxaziridines. Imines are intermediates in the alkylation of amines with formic acid in the Eschweiler-Clarke reaction . A rearrangement in carbohydrate chemistry involving an imine is the Amadori rearrangement .
22 hours ago
Imines derived from acyclic amines are usually unstable and undergo spontaneous nonenzymatic hydrolysis to the corresponding amine and aldehyde metabolites. Aldehyde metabolites, in many cases, are oxidized rapidly to carboxylic acids by aldehyde dehydrogenases.
5.Converting Unstable Imine-Linked Network into Stable Aromatic
Url:https://pubmed.ncbi.nlm.nih.gov/31318202/
5 hours ago
Efficiently converting unstable linkages into stable linkages is an important objective in the chemistry of covalent organic frameworks (COFs), because it enhances stability and preserves crystallinity. Here, an unstable imine-linked COF was converted into a stable aromatic benzoxazole-linked COF (B …
19 hours ago
An imine obtained from aldehyde may be unstable in chromatographic conditions and decompose on silica gel due to the acidity of silica. To solve this problem you may try three ways:
8 hours ago
To overcome this limitation, a strategy is reported here using dynamic imine chemistry for facile construction of imine-based macrocycle and cage upon treatment of a diamine with di- and tri-aldehydes respectively, followed by post-synthesis one-step conversion of imine bonds to amides to form the desired robust macrocycle and cage containing ...
17 hours ago
According to this paper, isoindole is unstable because the 1-carbon in the isoindolidine tautomer is very electron-deficient. I figured that the electron-deficiency of this carbon must be because it is bonded to an aromatic carbon and double bonded to a nitrogen, both of which atoms are electron-withdrawing. By this logic, I would expect other carbons in this situation (C (aryl)-C=N) to also …
19 hours ago
There are a number of reasons why the internet connection is unstable—it can be a hardware issue, a software issue, or both. The most common reason for the unstable connection is router malfunction due to faulty connection, faulty hardware, radio interference, or a weak signal.
33 hours ago
Why is imine unstable? Imine Formation One of the two shared pairs of electrons that constitute the double bond between C and O is transferred to O. ... This forms the characteristic C=N double bond, and the oxygen is concurrently eliminated as water. The loss of the hydroxyl group is difficult, as the resultant hydroxyl ion is unstable.
