为什么有机化学中的ortho、meta、para对应苯环的1,2、1,3、1,4 …
2019年7月6日 · 醇（Alcohol）和酚（Phenol），英文命名是不分的，都是加-ol后缀，例如甲醇（Methanol）、苯酚（Phenol）、萘酚（Naphthol）等，但中文分别命名为“醇（会意字）” …
Ortho-, Para- and Meta- Directors in Electrophilic Aromatic Substitution
2018年1月29日 · Examples of ortho-, para – directors are hydroxyl groups, ethers, amines, alkyl groups, thiols, and halogens. Here’s a concrete example: the nitration of methoxybenzene …
A para- to meta-isomerization of phenols - Nature Chemistry
2024年4月17日 · Here we describe a procedure to transpose phenols that hinges on a regioselective diazotization of the corresponding ortho-quinone. The procedure affords the …
Acidity of Substituted Phenols - Chemistry LibreTexts
2023年1月23日 · Substitution of the hydroxyl hydrogen atom is even more facile with phenols, which are roughly a million times more acidic than equivalent alcohols. This phenolic acidity is …
16.4 Substituent Effects in Electrophilic Substitutions
When phenol is nitrated, for instance, reaction can occur either ortho, meta, or para to the –OH group, giving the carbocation intermediates shown in Figure 16.15. The ortho and para …
organic chemistry - Activity of different positions in phenol with ...
2015年6月22日 · As the figure below illustrates, substituents on aromatic rings that are electron donating like the methyl and t-butyl groups (and also the hydroxy group [e.g. phenol]) increase …
A para- to meta-isomerization of phenols - PubMed
Here we describe a procedure to transpose phenols that hinges on a regioselective diazotization of the corresponding ortho-quinone. The procedure affords the meta-substituted phenol …
Overriding Ortho–Para Selectivity via a Traceless Directing Group …
2014年3月11日 · The direct functionalization of phenols at the ortho and para position is generally facilitated by the electron-donating nature of the hydroxyl group. Accessing meta …
A para- to meta-isomerization of phenols - McGill University
2024年4月17日 · The process involves oxygenation of the phenol to an ortho-quinone, followed by selective deoxygenation to provide the transposed product. Amongst the many examples …
Ir-Catalyzed ortho-Borylation of Phenols Directed by …
2017年4月28日 · A strategy for affecting ortho versus meta/para selectivity in Ir-catalyzed C–H borylations (CHBs) of phenols is described. From selectivity observations with ArylOBpin (pin …