pinacol-type couplings between two structurally similar aromatic aldehydes promoted by low-valenttitanium generated unsymmetrical pinacols in moderate to good isolated yields in an erythro/threo ratio of up to 91:9. This synthetic methodology significantly extends the scope of the cross pinacol-type couplings. pinacol - pinacol-type coupling - cross coupling - McMurry coupling - low-valenttitanium