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(10) A simple conformer search was performed using molecular
mechanics MMFF and revealed a preference for the cis-methyl sub-
stituent to eclipse the allylic hydrogen as in TS1.
’ AUTHOR INFORMATION
Corresponding Author
’ ACKNOWLEDGMENT
We thank NSERC (Canada), Merck (IRC), and the University of
Toronto for support of these studies. D.C. thanks NSERC for a CGS
D scholarship and Dr. Robert Webster (University of Toronto). J.P.
thanks NSERC for a CGS D scholarship. We also thank the reviewers
for their comments and suggestions.
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(9) After stirring for 24 h, LDA (0.5 equiv) was added, and the
reaction mixture was stirred for 1 h. TLC indicated that starting material
still remained, more LDA (1.0 equiv) was added, and the mixture was
stirred for 1 h; at this time, the reaction was deemed complete by TLC
analysis.
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