Acidity of substituted phenols - Chemistry Stack Exchange
网页2014年11月6日 · Phenol has a $\mathrm pK_\mathrm a$ approximately equal to $9.9$. When one studies the acidity of chlorophenols, one notices the following: First of all, chlorophenols are more acidic than phenol, due the negative inductive effect (−I) of chlorine, that reduces the negative charge, located on the oxygen of the phenolate anion.
Acidity order of nitrophenols - Chemistry Stack Exchange
网页2016年6月21日 · 24. As in other posts I have seen and learnt that, if one is given four compounds, namely para -nitrophenol, ortho -nitrophenol, meta -nitrophenol and phenol and is told to arrange them in order of acidity, then one has to take into account the $\text {-R}$ and $\text {-I}$ effect. Now, for the inductive effect, the greatest intensity is ...
organic chemistry - What is the order of acidic strength among …
网页2017年12月9日 · A quick search on says that resorcinol is more acidic that catechol, followed by phenol. Hydroquinone - strong +M effect and weak -I effect. Phenol - the normal resonance you'd expect in all phenols. Resorcinol - -I effect. Catechol - +M effect, stronger -I effect and hydrogen bonding
Inductive vs resonance effects and the acidity of phenol
网页2014年12月3日 · It turns out that an inductive effect—not a resonance effect—is the predominant reason for the increased acidity of phenol relative to aliphatic alcohols. For those interested, these data come from Evans’ Chem 206 lecture notes (Lecture 20, restricted access), where the point is hammered home in glorious detail.
Reason for the stronger acidic property of phenol than alcohol
网页In phenol, pulling the $\mathrm{p}_z$ electrons from the oxygen atom into the ring causes the hydrogen atom to be more partially positive than it is in aliphatic alcohols. This means it is much more easily lost from phenol than it is from aliphatic alcohols, so phenol has a stronger acidic property than ethanol.
organic chemistry - Why is acetic acid more acidic than phenol ...
网页2013年9月6日 · The $\text{p}K_{\text{a}}$ of ethanoic acid is $4.8$ while the $\text{p}K_{\text{a}}$ of phenol is $10$. So ethanoic acid is indead more acidic than phenol (for an explanation of $\text{p}K_{\text{a}}$ values and their connection to acid strength see my answer here). And this is only to be expected …
Acidity order of 4-halophenols - Chemistry Stack Exchange
网页Experimental acidic strength order: parabromophenol > paraiodophenol > parachlorophenol > parafluorophenol. At first, I thought of simply using the -I effect to determine the stability of these phenol derivatives. Since -I effect is shown best by fluoro group, therefore charge delocalisation would be best in the fluoro derivative's anion.
Acidic strength of nitrophenols - Chemistry Stack Exchange
网页2023年2月27日 · A comparison of p- (Entries 5, 8 & 13; mesomeric) and m-substitutions (Entries 4, 7, and 12; pure inductive) in all phenol derivatives, have shown the well known enhancement from mesomeric interaction of p-groups and inductive interaction of m-group effects, increasing the acidity in both cases (increasing the stability of the conjugate base ...
Acidity of phenol and carboxylic acid - Chemistry Stack Exchange
网页2020年7月22日 · It has a pKa p K a of 3.75 3.75. Now, as you mentioned, phenol (or carbolic acid) has a pKa p K a of 10.0 10.0. There is a difference of about 6 6 in the two values. This is because of the effective delocalization that takes place in formic acid compared to that of phenol. The best way to check for …
Why is p-methoxyphenol more acidic than p-methylphenol?
网页2015年3月15日 · I think the explanation of the substituent effects on the phenoxide are also sound. The explanation of the substituent effects on the phenol side is (admittedly) weak. Nonetheless, this explanation does correctly explain why p-methoxyphenol and p-methylphenol have comparable acidities and why these …