Comparison of catalytic activities for the transesterification of MA with 1b^a.

Entry	Catalyst	Yield [%] of 2bb
		6 h	8 h	12 h	19 h	24 h
1	Mg(BHT)2	62	85	91	99	—
2	Mg(PBTP)	90	99	—	—	—
3	Mg (TBP)c	35	42	—	—	60

^aUnless otherwise noted, the reaction was carried out using MA (14 mmol), 1b (2 mmol), catalyst (5 mol%), Cu(CS₂NMe₂)₂ (polymerization inhibitor, 0.2 mol%), and MS 5A (0.4 g) at 25 °C.

^bThe yield was determined via¹H NMR analysis using dimethylsulfone as an internal standard.

^cTBP-H₂ and Mg (TBP) are shown as follows.