Table 1.

Examination of chiral imidazolinium salts as catalyst precursors.^[a]

Entry	Imidazolinium Salt	Conv. [%][b]	Yield [%][c]	e.r.[d]
1	1a	53	46	84:16
2	1b	96	85	84:16
3	2a	>98	79	88:12
4	2b	68	54	67:33
5	3a	>98	74	91.5:8.5
6	3b	91	82	90:10
7	3c	>98	90	96:4

^[a]Reactions were performed under N₂ atmosphere.

^[b]Determined by analysis of 400 MHz ¹H NMR spectra of unpurified mixtures (±2%).

^[c]Yields of isolated and purified products (±5%).

^[d]Determined by GC analysis (±2%); see the Supporting Information for details. dbu = 1,8-diazabicyclo[5.4.0]undec-7-ene; Mes = 2,4,6-Me₃C₆H₂.