The reaction between bis(2‐benzothiazolyl) ketone (1) and a series of ring‐substituted phenyl Grignard reagents gives, in considerable amount, the unexpected O‐alkylation product derived from the attack of the Grignard reagent to thecarbonyl oxygen atom, thus extending the range of rarely reported cases in which O‐alkylation can occur. The expected classic 1,2‐addition product and that derived from O‐alkylation have been obtained in a relative molar ratio dependent on the substituent on the phenyl ring. Bis(2‐benzothiazolyl) aryl carbinols, the classic 1,2‐addition products to the carbonyl group of 1, were obtained in high yield through an alternative synthetic route that permitted the limit imposed by O‐ vs. C‐alkylation competition to be overcome.