Table 3.

Stereoselective addition of phenylacetylene to a series of α-chloroketones promoted by (R,R)-Salen ligand.

Entry a	Ketone	dr b	T (h)	ee anti c	ee syn c	Yield d ( syn + anti)
1	1a	82:18	60	90	82	26
2	1b	73:27	120	85	65	35
3	1c	77:23	60	81	58	25
4	1d	78:22	60	82	55	18
5	1e	75:25	140	62	42	40
6	1f	80:20	60	83	57	17

^a All the reactions were performed at −20 °C under nitrogen and stopped after the time indicated. ^b The diastereoisomeric ratios were evaluated on the crude reaction mixture by ¹H-NMR. ^c The enantiomeric excess was evaluated by chiral HPLC analysis (see experimental part for the conditions) ^d Isolated yield (syn + anti) after chromatographic purification.