The Ivanov reaction is a reaction that is used in organic synthesis to obtain compounds with physiological activity. The reaction was discovered by the Bulgarian chemist Dimitar Ivanov Popov in 1931.
It is a method for the preparation of β-hydroxycarboxylic acids with the general formula —CR (OH) —CR1 (COOH) - from carbonyl compounds and Ivanov’s reagents: magnesium halogen derivatives of aryl acetic acid salts (usually phenylacetic acid ) [1] . For example:
{\ displaystyle {\ mathsf {R \! \! - \! \! CO \! \! - \! \! R + [Ar \! \! - \! \! CH ^ {-} \! \! \! \! - \! \! COONa] MgCl ^ {+}}} \ rightarrow {\ mathsf {[Ar \! \! - \! \! CR (COONa) \! \! - \! \! CHR (OMgCl) ]}} \ rightarrow {\ mathsf {Ar \! \! - \! \! CR (COOH) \! \! - \! \! CHROH}}}
![{\ mathsf {R \! \! - \! \! CO \! \! - \! \! R + [Ar \! \! - \! \! CH ^ {-} \! \! \! \! - \! \! COONa] MgCl ^ {+}}} \ rightarrow {\ mathsf {[Ar \! \!! - \! \! CR (COONa) \! \! - \! \! CHR (OMgCl)]}} \ rightarrow {\ mathsf {Ar \! \! - \! \! CR (COOH) \! \! - \! \! CHROH}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/ac338f015e3b2ba9bb5f4c364b3fcdeb6a9fe005)
(Ar is phenyl, chlorophenyl; R is H, Alk, Ar, OPh). Aliphatic or aromatic aldehydes and ketones, as well as cycloalkanones, ketosugar and camphor, react. As a result of the reaction, as a rule, a mixture of erythro and mreo isomers of b-hydroxycarboxylic acid is formed. Ivanov's reagents are prepared by the action of 2 moles of R'MgX (most often iso-C3H7MgCl) per 1 mol of aryl acetic acid (usually PhCH2COOH) or 1 mol of R'MgX per 1 mol of its sodium salt. Depending on the reaction conditions and the structure of the starting compounds, Ivanov’s reagents can have the structure of an enolate (f-la I) or contain a C – Mg bond (f-la II).
If necessary, the hydroxy acid can be easily converted to the corresponding alcohol by decarboxylation.
See also
- Obtaining Alcohols
Notes
- ↑ Ivanova reaction // Chemical Encyclopedia / Editor-in-chief I. L. Knunyants. - M .: "Soviet Encyclopedia", 1988. - T. 2. - S. 344-345.