Table 3. Apparent Rate Constants (k_obs) for the Polymerization of rac-Lactide^a.

entry	cat.	kobs (h–1)	entry	cat.	kobs (h–1)
1	2a	0.248 (±0.009)	5	2g	0.173 (±0.006)
2	2c	0.11 (±0.04)	6	2h	0.21 (±0.04)
3b	2c	0.09 (±0.02)	7	2i	0.17 (±0.06)
4	2e	0.16 (±0.01)

^aThe kinetic experiments were run in the presence of 1 equiv of BnOH (vs Al catalysts); see Experimental section for details.

^bl-Lactide was used.