Organic chemistry /Chemical bonding
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jai shri ram
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Organic chemistry /Chemical bonding
How is this the answer wont the oxygen give backbonding making bmore stable plz answer
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ChenBeier
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Re: Organic chemistry /Chemical bonding
Opposit ist the case:
2-Phenyl-1,3-dithiolane possesses a relatively acidic proton at the
position due to the stabilizing effect of the two adjacent sulfur atoms and the conjugated phenyl group, allowing for deprotonation by strong bases (e.g.,
-BuLi) to form a stable carbanion. It is generally stable under acidic and basic conditions.
Key Acidity and Reactivity Aspects:
Deprotonation: The proton at
(between the two sulfur atoms) can be removed by organolithium reagents, a key step in "umpolung" (polarity reversal) reactions.
Stability: Unlike acetals, 1,3-dithiolanes are resistant to hydrolysis, requiring harsh conditions or specific metal catalysts (like
or cadmium carbonate) for cleavage.
Comparison: While 2-phenyl-1,3-dithiolane is acidic at the
position, it is generally considered less acidic than its 1,3-dithiane counterpart (six-membered ring) because the five-membered ring structure provides less effective carbanion stabilization.
2-Phenyl-1,3-dithiolane possesses a relatively acidic proton at the
position due to the stabilizing effect of the two adjacent sulfur atoms and the conjugated phenyl group, allowing for deprotonation by strong bases (e.g.,
-BuLi) to form a stable carbanion. It is generally stable under acidic and basic conditions.
Key Acidity and Reactivity Aspects:
Deprotonation: The proton at
(between the two sulfur atoms) can be removed by organolithium reagents, a key step in "umpolung" (polarity reversal) reactions.
Stability: Unlike acetals, 1,3-dithiolanes are resistant to hydrolysis, requiring harsh conditions or specific metal catalysts (like
or cadmium carbonate) for cleavage.
Comparison: While 2-phenyl-1,3-dithiolane is acidic at the
position, it is generally considered less acidic than its 1,3-dithiane counterpart (six-membered ring) because the five-membered ring structure provides less effective carbanion stabilization.