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O
OSiPh2tBu
1) base (1.6 equiv.), -78°C, 30 min
2) TBDPSCl (1.2 equiv.), -78°C-rt, 2 h
3) sat. NaHCO3 (aq)
entry
base
yield
a
b
c
LTMP 24% (40% cyclohexone recovered)
LHMDS 23% (43% cyclohexone recovered)
5. (a) Bailey, A. D.; Cherney, S. M.; Anzalone, P. W.; Anderson, E. D.; Ernat, J. J.;
Mohan, R. S. Synlett 2006, 215–218; (b) Sun, J.; Dong, Y.; Cao, L.; Wang, X.;
Wang, S.; Hu, Y. J. Org. Chem. 2004, 69, 8932–8934.
KHMDS
94%
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