Adduct

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Adduct is a term used in chemistry and physics for a compound molecule. No by-products such as water or alcohol are produced in the reactions to form the adduct. A distinction is made between a .:

  • Adduct between Lewis acid and Lewis base : Covalently bonded molecules from an electron donor (e.g. Et 2 O) and an electron acceptor (e.g. BF 3 ): Et 2 O + BF 3 → Et 2 O-BF 3
  • non-covalently bound adducts: e.g. B. cation or anion addition complexes in electrospray ionization - mass spectrometry . Ligands (e.g. solvent molecules, peptides, proteins, other analytes) are arranged around a cation or anion (e.g. H + , Na + or HCOO-). The number of ligands depends on the electrical charge, the ion size, the ligand strength and the experimental conditions. This type of adduct is also called a cluster .
  • DNA adducts : electrophilic molecules can bind covalently with the free electron pairs of the bases present in DNA (Lewis complex) and thereby e.g. B. prevent cell division or trigger mutations (e.g. malondialdehyde , 4-hydroxynonenal ).
  • Diels-Alder adduct: product of a Diels-Alder reaction .
  • Michael adduct: product of the Michael addition .
  • Pi adduct : the product of a reaction in which a directed interaction between a π orbital and a π or σ orbital leads to a new bond (e.g. in the reaction between a platinum atom and ethylene or in an intermediate in electrophilic substitution on aromatics).
  • Sigma adduct (formerly sigma complex): the product that is created by the addition of an electrophilic or nucleophilic group or a radical to a ring carbon of an aromatic species to form a new sigma bond. The term is also used for adducts with unsaturated and conjugated compounds in general.
  • Meisenheimer complex (also Jackson – Meisenheimer adduct): a cyclohexadienyl derivative consisting of a nucleophile and a (hetero-) aromatic component.

Individual evidence

  1. ↑ Entry on adduct . In: IUPAC Compendium of Chemical Terminology (the “Gold Book”) . doi : 10.1351 / goldbook.A00138 Version: 2.3.2.
  2. ↑ entry to Lewis adduct . In: IUPAC Compendium of Chemical Terminology (the “Gold Book”) . doi : 10.1351 / goldbook.L03510 Version: 2.3.2.
  3. ↑ Entry on adduct ion in mass spectrometry . In: IUPAC Compendium of Chemical Terminology (the “Gold Book”) . doi : 10.1351 / goldbook.A00139 Version: 2.3.2.
  4. ↑ Entry on π-adduct . In: IUPAC Compendium of Chemical Terminology (the “Gold Book”) . doi : 10.1351 / goldbook.A04388 Version: 2.3.2.
  5. ↑ Entry on σ-adduct . In: IUPAC Compendium of Chemical Terminology (the “Gold Book”) . doi : 10.1351 / goldbook.A05436 Version: 2.3.2.
  6. ↑ Entry on Meisenheimer adduct . In: IUPAC Compendium of Chemical Terminology (the “Gold Book”) . doi : 10.1351 / goldbook.M03819 Version: 2.3.2.