. Author manuscript; available in PMC: 2011 Sep 3.

Published in final edited form as: Org Lett. 2010 Sep 3;12(17):3764–3767. doi: 10.1021/ol101388h

Table 2.

Double Diastereoselective NCAL Reactions with Enantioenriched Aldehyde Acids 9b-e


entry	carbocycle fused bicyclic β-lactones	NEt₃ % yield (dr)^a,^b	O- TMSQD % yield (dr)^b,^c	O- TMSQN % yield (dr)^b,^c
1^d		55	82, 92% ee^e	42, 90% ee^f
2		84 (1:>19)	33 (1:>19)	23 (1:>19)
3		45 (2:1)	32 (1:3)	55 (10:1)
4		38 (2:1)	31 (1:>19)	10 (>19:1)

Reaction run for 12-24 h at 0.05 M.

Yields refer to isolated, purified products and diastereomeric ratios were determined by ¹H NMR (500 MHz) analysis (integration) of the crude reaction mixtures.

Reaction run for 48-72 h at 0.20 M.

Previously described (see refs. ^4b,c) enantioselective NCAL process with an achiral substrate shown for comparison.

Reaction run with O-AcQD.