Allyls

Part of speech: noun

Definitions

1. A type of unsaturated hydrocarbon radical derived from propene by removing a hydrogen atom from the carbon adjacent to a double bond; used in organic synthesis ; a group attached to molecules influencing reactivity and physical properties
2. A chemical moiety featuring a carbon-carbon double bond next to a methylene group, often acting as a substituent in compounds ; involved in reactions such as polymerization and substitution ; influencing chemical behavior due to its structure
3. An organic fragment characterized by a vinyl group connected to a methylene unit, frequently found in various chemical compounds ; serving as a key intermediate in synthetic pathways ; known for its conjugated double bond system affecting stability and reactions

Etymology: The name comes from garlic. In 1844, the German chemist Theodor Wertheim isolated a compound from oil of garlic, and chemists then needed a name for the radical it contained. The Latin word for garlic is "allium," and the suffix "-yl," a standard chemists' ending for radicals (the term "radical" is used here in its older chemical sense of a group of atoms that passes unchanged through reactions), was attached to make "allyl." Allyl is therefore a naming choice rather than a discovery about the group's structure. The name records where the substance was first found, not what the group looks like, so a chemist reading "allyl" learns nothing about the double bond from the word itself. The term is a Latin root plus an English chemical suffix, a pattern common among the organic radical names of the nineteenth century.

Synonyms: alkenyl, prop-2-en-1-yl