The rates of the asymmetric hydrogenation of prochiral diketones catalyzed by Ru(BINAP) catalysts were substantially accelerated in the presence of small amounts of a strong acid.
Fan, Q. H., Yeung, C. H., & Chan, A. S. C. (1997). An improved synthesis of chiral diols via the asymmetric catalytic hydrogenation of prochiral diones. Tetrahedron Asymmetry, 8(24), 4041–4045. https://doi.org/10.1016/S0957-4166(97)00555-7