Multigram-scale (Amano PS-IM)-catalyzed KR of rac-4 with vinyl acetate in TBME at 50 °C.

Entry	Scale (g)	t (h)	Conv.a (%)	eesb (%)/yieldc (%)	eepb (%)/yieldc (%)	E d
1	2.5e	23	57	>99/40	74/48	34
2	5.0f	24	58	>99/39	73/55	32

^aBased on GC, for confirmation, the % conversion was calculated from the enantiomeric excess of the unreacted alcohol (ee_s) and the product (ee_p) according to the formula conv. = ee_s/(ee_s + ee_p).

^bDetermined by chiral HPLC analysis.

^cIsolated yield after column chromatography using a gradient of a mixture of CHCl₃/acetone (98 : 2, 95 : 5 v/v).

^dCalculated according to Chen et al.,²⁶ using the equation: E = {ln[(1 − conv.)(1 − ee_s)]}/{ln[(1 − conv.)(1 + ee_s)]}.

^eConditions: rac-4 2.5 g, Amano PS-IM 1.25 g (50% w/w), TBME 50 mL, vinyl acetate 2.7 g, 2.88 mL (3 equiv.), at 50 °C, 800 rpm (magnetic stirrer).

^fConditions: rac-4 5 g, Amano PS-IM 1.25 g (25% w/w), TBME 100 mL, vinyl acetate 5.4 g, 5.77 mL (3 equiv.), at 50 °C, 800 rpm (magnetic stirrer).