Table 1.

Catalytic enantioselective synthesis of oxygen heterocycles by chiral bidentate and monodentate phosphines.

entry	cat.	ee (%)[a]	yield (%)[b]
1	(S,S)-CHIRAPHOS	-	<2
2	(R,R)-DIPAMP	22	70
3	(R,R)-Me-DUPHOS	-	<2
4	(R,R)-BINAPHANE	17	9
5	(R)-MOP	-	<2
6	(S)-MONOPHOS	-	<2
7	(S)-4	−66	72
8	(S)-5	−45	65
9	(S)-1	87	80

All data are the average of two experiments.

^[a]A negative value for the ee signifies that the enantiomer of 3 is formed preferentially.

^[b]The yield was determined by GC analysis with the aid of a calibrated internal standard.