Hemiketals

Part of speech: noun

Definitions

  1. Chemical compounds formed when an aldehyde or ketone reacts with an alcohol, creating a functional group featuring a carbon bonded to both a hydroxyl and an alkoxy group ; structures often acting as intermediates or stable species in organic synthesis and carbohydrate chemistry ; molecules characterized by a central carbon atom connected simultaneously to an -OH group and an -OR group derived from the addition reaction of carbonyls with alcohols
  2. Organic species resulting from the nucleophilic addition of an alcohol to a carbonyl carbon, producing a carbon atom attached to one hydroxyl and one alkoxy substituent ; intermediates in the processes of carbohydrate ring formation and important in the study of glycosides ; chemical entities possessing both alcohol and ether functionalities bound to the same carbon center formed from ketones or aldehydes and alcohols
  3. Compounds generated by the interaction between aldehydes or ketones and alcohols, characterized by a central carbon bearing both a hydroxyl and an alkoxy group ; frequently involved in the structural chemistry of sugars and important as reaction intermediates ; molecules exhibiting dual functional groups on a single carbon including one from an alcohol and another from an ether linkage

Etymology: Hemiketals are a class of chemical compounds, and the word is simply a chemist's construction built from two pieces. The first, "hemi-", comes from Ancient Greek "hēmi-", meaning "half" (it is related to the Greek word for "half" that also gives English "semi-"). The second, "ketal", is a name built on "ketone", the family of carbon compounds that includes acetone. The word is a plain compound: "hemi-" attached to "ketal" yields a compound that is half of a ketal. A ketal forms when a ketone reacts with alcohol and loses water. A hemiketal is the intermediate stage, where only one alcohol group has joined the ketone, so the molecule is only half-way to a full ketal. Chemists use the prefix in the same way for other partial structures, such as hemiacetals, which are the half-formed versions of acetals.

Synonyms: hemiacetals