Surf Wiki
Save to docs
general/functional-groups

From Surf Wiki (app.surf) — the open knowledge base

Methylene bridge

Any part of a molecule with the chemical formula –CH2–

Methylene bridge

Any part of a molecule with the chemical formula –CH2–

The methylene bridge (methanediyl group)

In chemistry, a methylene bridge is part of a molecule with formula . The carbon atom is connected by single bonds to two other distinct atoms in the rest of the molecule. A methylene bridge is often called a methylene group or simply methylene, as in "methylene chloride" (dichloromethane ). As a bridge in other compounds, for example in cyclic compounds, it is given the name methano. However, the term methylidene group (not to be confused with the term methylene group, nor the carbene methylidene) properly applies to the group when it is connected to the rest of the molecule by a double bond (), giving it chemical properties very distinct from those of a bridging group.

Organic chemistry

It is the repeating unit in the skeleton of the unbranched alkanes. Polyethylene also can be called polymethylene.

Compounds possessing a methylene bridge located between two electron withdrawing groups (such as nitro, carbonyl or nitrile groups) are sometimes called active methylene compounds. Treatment of these with strong bases can form enolates or carbanions, which are often used in organic synthesis. Examples include the Knoevenagel condensation and the malonic ester synthesis.

Examples of compounds that contain an activated methylene bridge include: File:Malonsäure.svg|Malonic acid File:Acetyloaceton.svg|Acetylacetone File:Malononitrile.png|Malononitrile

Inorganic and organometallic chemistry

A methylene bridge can be a ligand joining two metals. Titanium and aluminum are linked by a methylene bridge in Tebbe's reagent.

Nomenclature

Methylene bridge is sometimes called a methylene spacer or methanediyl group.

References

References

  1. "Active methylene compound".
  2. House, Herbert O.. (1972). "Modern Synthetic Reactions". W. A. Benjamin.
  3. W. A. Herrmann (1982), "The methylene bridge". In ''Advances in Organometallic Chemistry'', volume 20, pages 195-197.
Info: Wikipedia Source

This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page.

functional-groups
Want to explore this topic further?

Ask Mako anything about Methylene bridge — get instant answers, deeper analysis, and related topics.

Research with Mako

Free with your Surf account

Content sourced from Wikipedia, available under CC BY-SA 4.0.

This content may have been generated or modified by AI. CloudSurf Software LLC is not responsible for the accuracy, completeness, or reliability of AI-generated content. Always verify important information from primary sources.

Report