Table 5.

Catalytic Enantioselective [3+2] Cycloadditions of γ-Substituted Allenes with an Oxygen-Substituted Olefin^a

entry	R	ee (%)	drb	yield (%)c
1	Me	96	10: 1	79
2	n-Pr	89	11: 1	85
3		86	12: 1	83

^aAll data are the average of two experiments. For the determination of structure, including stereochemistry, see the Supporting Information.

^bDetermined by ¹H NMR analysis of the unpurified reaction mixture; for each cycloaddition, the ratio of regioisomers is ≥20:1.

^cYield of purified product (dr ≥ 12: 1).