We then investigated whether principles used in 2-deoxyβ-glucosylations could be applied to the more challenging 2,6-dideoxy-β-glucosylations. Disarmed diacetoxy-substituted derivatives were too unstable for isolation and application in the catalytic reaction, so we evaluated a series of 2,6-dideoxy-L-glucose derivatives with various protecting group schemes and phosphate leaving groups. Bis-trichloroacetyl (TCA) derivative 7a was identified as displaying the best compromise between reactivity and stability. Threonine derivative 3a displayed poor reactivity as a nucleophile, so tyrosine derivative 4a was used as the model substrate in catalyst optimization studies to enable accurate determination of α/β-selectivities by 1 H-NMR analysis of crude reaction mixtures. In a survey of bis-thioureas with different arylpyrrolidine substituents, the 2-naphthyl substituted ent-1b, previously effective in site-selective glycosylations, provided the best yields and β-selectivity (Fig-