Table 2.

Evaluation of ligand structure in additions of MeLi to imine 8

entry	R4	ligand	temp, °C	yield, %a	erb
1	CH2Ph	12ba	−78	91	67.0:33.0
2	CHMe2	12bb	−78	90	85.0:15.0
3	CMe3	12bc	−94	32	84.0:16.0
4	CMe3	12bc	−78	95	87.5:12.5
5	CMe2Ph	12bd	−78	75	82.0:18.0
6	CMePh2	12be	−78	41	89.0:11.0
7	CMePh2	12be	−63	99	90.5:9.5
8	CPh3	12bf	−63	0	–

^aYield of chromatographically homogeneous material.

^bAll compounds have R configuration. Determined by CSP-HPLC analysis.