TheCannizzaro Reaction

Abstract

The reaction in which two aldehyde groups are transformed into the corresponding hydroxyl and carbonyl functions, existing separately or in combination as an ester, has been termed the Cannizzaro reaction. Here the discussion is restricted to the dismutation of two similar aldehyde groups into the corresponding alcohol and carboxylic salt function by means of aqueous or alcoholic and alkali. The conversion of benzaldehyde into a mixture of benzyl alcohol and sodium benzoate is an example.

Transfer Hydrogenation and Hydrogenation of Commercial‐Grade Aldehydes to Primary Alcohols Catalyzed by 2‐(Aminomethyl)pyridine and Pincer Benzo[h]quinoline Ruthenium Complexes

“…Aldehydes, which have a formyl group, show a broader reactivity than ketones. Under basic conditions, aldehydes may undergo the Claisen–Tishchenko (dimerization) and Cannizzaro reactions (Scheme ).…”

Transfer Hydrogenation Including the Meerwein‐Ponndorf‐Verley Reduction

“…In the Cannizzaro reaction [110,111] two aldehyde functionalities disproportionate into the corresponding hydroxyl and carboxyl functions, either as separate compounds or as an ester (Scheme 20.25). The reaction conditions needed are rather harsh, except when R 1 or R 2 is a phenyl group.…”

Synthesis of the seco‐Limonoid BCD Ring System Identifies a Hsp90 Chaperon Machinery (p23) Inhibitor

“…Although this set of conditions was capricious, the desired diastereomer ( 18 ) was regularly obtained in yields greater than 40 % (i.e., setting up the functionalized BC ring system), the undesired diastereomer ( 19 ) in 29 % yield, along with recovered starting material (10 % yield). Fortunately, these could be recycled via retro‐aldol by treatment with base in 68 % yield, although the reduced ketone 20 was obtained as a minor by‐product (10 %) as a result of a Cannizzaro reaction of a minor diastereomer . In readiness to evaluate the pharmacophore capacity of the furan ring within this system, intermediate 17 was also subjected to an aldol reaction with formaldehyde.…”