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Glite Dictionary
hemiacetal

hemiacetal

9.9
A compound formed when an aldehyde or ketone reacts with an alcohol
  • noun
  • /ˌhɛmɪəˈsɛtəl/
  • Specialized
: hemiacetal
  • The reaction produced a hemiacetal as an intermediate before forming the final product.

Examples

  • In carbohydrate chemistry, the ring form of glucose is actually a hemiacetal.

  • The hemiacetal forms quickly in the presence of alcohol.

  • The stability of a hemiacetal depends on the specific structure of the molecule.

  • Is a hemiacetal stable at room temperature?

  • In carbohydrate chemistry, the ring form of glucose is actually a hemiacetal.

  • The reaction produced a hemiacetal as an intermediate before forming the final product.

  • The hemiacetal forms quickly in the presence of alcohol.

Surface Forms

hemiacetal singular
hemiacetals plural

Morphology

hemiacetal = acetal (semi-transparent) = hemi + acetal

Formally 'hemi-' (half) + 'acetal' indicates a 'half-acetal' intermediate, but the term is technical and its exact chemical sense requires domain knowledge.

Etymology

Hemiacetal comes from Greek hemi- meaning 'half' and acetal, a chemical name, and you can remember hemi- from hemisphere, which also means 'half'. So a hemiacetal is a 'half' acetal — an in-between or half-formed chemical that appears before the full acetal is made.