Table 3. Effect of Different Catalyst Substituents on the Yield of the Ring-Opening Reaction and ee of the Products.

entry	catalyst	solvent	temp (°C)	time (h)	yield (%)a	head (%)b,c
1	1j	toluene	–30	24	87	30
2	1m	toluene	–30	24	98	92
3	1o	toluene	–30	24	87	30
4	1n	toluene	–30	24	82	13
5	1o	toluene	–30	24	83	6
6	1o	toluene	–30	24	83	33
7	1p	toluene	–30	24	87	30
8	1q	toluene	–30	24	85	17
9	1r	toluene	–30	24	87	6
10	1s	toluene	–30	24	87	60
11	1a	toluene	–30	24	90	12
12	1t	toluene	–30	24	90	25
13	1m	CH2Cl2	–30	24	90	69
14	1m	hexane	–30	24	93	49
15	1m	toluene/CCl4	–30	24	84	27
16	1m	THF	–30	24	84	27
17	1m	diethyl ether	–30	24	85	29

^aIsolated yield of products.

^bDetermined by GC using the Agilent HP-1 column (19091Z-413, 30 m × 0.32 mm × 0.25 μm); conditions: initial temp, 50 °C; initial time, 3 min; 25.0 °C/min; final temp, 280 °C; 17 psi; retention time, 10.76 14.12 min.

^cAbsolute configuration.⁸