imido group
C2Technical/Scientific
Definition
Meaning
A functional group in chemistry consisting of two acyl groups bonded to nitrogen, -NR(CO)₂, often derived from ammonia or a primary amine.
In organic and inorganic chemistry, a bivalent group =NH attached to two carbonyl groups or other electron-withdrawing moieties, forming part of larger molecules like imides or coordination complexes.
Linguistics
Semantic Notes
The term is highly specific to chemistry. It refers to a structural unit, not a standalone substance. It can appear as a bridging ligand in metal complexes or within cyclic organic compounds like phthalimide.
Dialectal Variation
British vs American Usage
Differences
No spelling or significant usage differences. Pronunciation of 'group' may have a slightly more pronounced /r/ in some American accents.
Connotations
Identical technical connotations in both varieties.
Frequency
Extremely low frequency in general language, used exclusively in chemical literature and discourse with identical frequency across varieties.
Vocabulary
Collocations
Grammar
Valency Patterns
The [compound] features a terminal/bridging imido group.The imido group [verb, e.g., acts as, bridges, coordinates]...Substitution at the imido group nitrogen.Vocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Usage
Context Usage
Business
Virtually never used.
Academic
Exclusively used in advanced chemistry research papers, textbooks, and lectures.
Everyday
Never used.
Technical
Core term in synthetic, organic, inorganic, and organometallic chemistry discussions and publications.
Examples
By Part of Speech
adjective
British English
- The imido-bridged complex was characterised by X-ray diffraction.
- We studied the imido group transfer reaction.
American English
- The imido-bridged complex was characterized by X-ray crystallography.
- We studied the imido group transfer reactivity.
Examples
By CEFR Level
- The researcher explained that the molecule contained a special nitrogen unit called an imido group.
- Imido groups are important in some industrial chemical processes.
- The catalytic cycle involves the formation of a reactive metal-imido group intermediate.
- The stability of the imido group is highly dependent on the substituents on the nitrogen atom.
- Spectroscopic data confirmed the presence of a terminal imido group in the organometallic complex.
Learning
Memory Aids
Mnemonic
Imagine 'I'm Ido' (I am Ido) holding two carbon-oxygen (C=O) balloons. The 'I'm' sounds like 'im-' and Ido is the nitrogen holding the two balloons, representing the two acyl groups.
Conceptual Metaphor
A structural keystone or bridge (as it often connects two parts of a molecule).
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Do not confuse with 'аминогруппа' (amino group).
- The Russian term 'имидная группа' is a direct equivalent.
- Avoid literal translation as 'имидо группа' – the standard chemical term is 'имидная группа'.
Common Mistakes
- Confusing 'imido' with 'imino' (C=NH).
- Using it as a countable noun for a free molecule rather than a substituent part of one.
- Incorrect stress on the second syllable (e.g., /ɪˈmiːdoʊ/).
Practice
Quiz
An 'imido group' is most specifically characterised by which of the following?
FAQ
Frequently Asked Questions
Not exactly. An 'imide' is a complete compound containing the imido group (usually as -CO-NR-CO- in a ring or chain). The 'imido group' specifically refers to the =NR unit (where R can be H, alkyl, etc.) within that larger structure.
Yes. Imido groups are prominent in inorganic and organometallic chemistry as ligands, often bridging two metal centres (µ-imido) or bonded terminally to a single metal (M=NR).
The standard pronunciation is /ˈɪmɪdoʊ/ (IM-i-doh). The stress is on the first syllable.
It is a key functional group in polymers (like polyimides), pharmaceuticals, and as a reactive intermediate in catalytic processes such as amination and aziridination, making it crucial for synthesising nitrogen-containing compounds.