Table 2. Polymerization of rac-Lactide with Al Complexes under Bulk Conditions^a.

entry	cat.	cat. loading (mol %)	time (h)	conversn (%)b	Mnc	Mnd	Mw/Mnd	Pr/Pme
1	2a	2	1.5	74	5.33	3.9 (2.3)	1.74	Pr = 0.52
2	2a	0.25	1.0	81	46.7	23.1 (13.4)	1.45	Pr = 0.52
3	2c	0.25	1.0	65	37.5	13.1 (7.6)	2.02	Pm = 0.61
4	2e	0.25	1.0	61	35.2	4.2 (2.5)	1.82	Pr = 0.57
5	2f	0.25	2.0	31	17.9	19.6 (11.3)	1.95	Pr = 0.60
6	2g	0.25	2.0	78	44.9	35.6 (20.6)	2.99	Pm = 0.57
7	2i	0.25	1.5	75	43.2	207 (120)	1.84	Pr = 0.58

^aReaction conditions: see the Experimental Section for details.

^bMonomer conversion determined by ¹H NMR spectroscopy.

^cCalculated molecular weight based on conversion: [LA]₀/[Al]₀ × (conversn %) × 144.

^dExperimental molecular weight determined by GPC vs polystyrene standards. The values in parentheses are corrected by a factor of 0.58.

^eProbability of racemic (P_r) or meso (P_m) enchainment, determined by homonuclear decoupled ¹H NMR spectroscopy.