A general and versatile method for the preparation of a variety of β-hydroxybenzothiazoles (aldol-type adducts) by the reaction of α-lithio-2-methylbenzothiazole with carbonyl compounds was proposed. As an example of the use of α-lithio-2-methylbenzothiazole as a masked enolate, the product obtained by the reaction of this lithium reagent with 5-chloro-2-pentanone could be effectively transformed into the corresponding β-oxyaldehyde [2-methyl-2-(2-oxoethyl)-tetrahydrofuran].