J. Am. Chem. Soc. Supporting Information S 1 Supporting Information Rh-Catalyzed Carbonyl Hydroacylation: An Enantioselective Approach to Lactones Zengming Shen, Hasan A. Khan, and Vy M. Dong* Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, M5S 3H6, CANADA. vdong@chem.utoronto.ca Table of Contents Page I. General procedures S 2 II. Methods for substrate synthesis S 4 III. Representative procedure for enantioselective rhodium- catalyzed hydroacylations of ketones S 8 IV. The X-ray crystal structure of (S)-9b and associated data S 13 V. Spectral data and HPLC traces S 21 I. General procedures Commercial reagents were purchased from Sigma Aldrich, Strem, or Alfa Aesar and were purified prior to use following the guidelines of Perrin and Armarego. 1 All reactions were carried out under nitrogen or argon atmosphere unless otherwise indicated. Reactions were monitored using thin-layer chromatography (TLC) on EMD Silica Gel 60 F 254 plates. Visualization of the developed chromatogram was performed by fluorescence quenching or KMnO 4 stain. Organic solutions were concentrated under reduced pressure on a Büchi rotary evaporator. 1 H and 13 C NMR spectra were recorded on any of three instruments: a Varian Mercury 300 and a Varian Mercury 400, both equipped with 1 Perrin, D. D.; Armarego, W. L. F. Purification of Laboratory Chemicals; 5 th ed., Pregamon Press, Oxford, 1988.