# Why methoxy group acts similar to trifluoromethyl in nucleophilic aromatic substitution

In an online test, the following question was asked:

The answer to this question was:

I totally agree with the answer, as $$\ce{OCH_3}$$ is an EDG, hence it will tend to form meta product in this reaction.

While reading NAS on Master Organic Chemistry, I came up to this article:

This article says that $$\ce{OCH_3}$$ behaves similar to $$\ce{CF_3}$$, but I can't figure out the possible reason. Any help is appreciated!

Related (unanswered) question: Nucleophilic substitution in aromatic compounds

• 1) although the use here is technically correct, usually "nucleophilic aromatic substitution" refers to SNAr mechanism. 2) for a benzyne mechanism, resonance effects do not matter, only inductive. This is covered in typical organic chemistry textbooks. – orthocresol Aug 4 at 15:53

## 1 Answer

Normally during a nucleophillic aromatic substitution reaction one of oxygen's lone pairs would delocalize across the ring, the existence of a triple bond here prevents this from happening so oxygen actually ends up acting like an EWG.

• " the existence of a triple bond here prevents this" - Can you please elaborate? – rv7 Aug 5 at 5:38