(organic chemistry) Any of a class of compounds of general formula R1R2C(OH)OR' (where R' is not H and R1 or R2 is often hydrogen).
(chemistry) any hemiacetal derived from a ketone
an organic compound usually formed as an intermediate product in the preparation of acetals from aldehydes or ketones
A hemiacetal or a hemiketal have the general formula R1R2C(OH)OR, where R1 or R2 is hydrogen or an organic substituent. They generally result from the addition of an alcohol to an aldehyde or a ketone, although the latter are sometimes called hemiketals.