Journal of the American Chemical Society
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ASSOCIATED CONTENT
Detailed synthetic procedures, compound characterization, NMR spec-
tra, X-ray crystallographic data, and computational details are provided.
This material is available free of charge via the Internet at
AUTHOR INFORMATION
equal contribution# from Y.W. and X.H.
Corresponding Author
hegang@nankai.edu.cn, pengliu@pitt.edu, gongchen@nankai.edu.cn,
The authors declare no competing financial interest.
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4436.
ACKNOWLEDGMENT
G.C. and G. H. thanks NSFC-21421062, -21672105, -21725204,
and -91753124 and Laviana for financial support of the experimental
part of this work. P.L. thanks the NSF (CHE-1654122) for financial
support for the computational part of the work. C.A.M.R. acknowl-
edges an NSF research fellowship (DGE-1747452). Calculations
were performed at the Center for Research Computing at the Uni-
versity of Pittsburgh and the Extreme Science and Engineering Dis-
covery Environment (XSEDE) supported by the National Science
Foundation.
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40. For comparative studies of C-H epimerization of 20-cis under other
conditions: 20-trans (3%) + 20-cis (96%) under 365 nm UV irradiation
o
in acetone at 35 C for 3 d (see ref 26); 20-trans (7%) + 20-cis (91%)
under 254 nm UV irradiation with HgBr2 (0.67 equiv) in cyclohexane at
o
35 C for 3 d (see ref 25); 20-trans (15%) + 20-cis (83%) under UV
o
irradiation (365 nm) with decatungstate (1 mol%) in CH3CN at 35 C
o
for 3 d (see ref 27); Complete decomposition 20-cis of at 220 C with
10% Pd/C in toluene for 3 h (see ref 28). See SI for details.
41. The highlighted C-H bond of 24-cis is also deactivated by the adjacent
OBz group.
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