10.1002/ejoc.201801804
European Journal of Organic Chemistry
COMMUNICATION
mmol, 1 equiv.) was added at -78 ˚C as a solution in THF (2 mL). The
reaction was removed from the bath after an additional 15 minutes and
allowed to warm to room temperature while stirring for 3 hours. The
reaction was quenched with 0.2 ml sat. NH4Cl and concentrated under
reduced pressure and isolated by column chromatography, eluting with
hexanes/ethyl acetate.
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General Procedure for Benzyl Addition to (R)-N-tert-Butanesulfinyl
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bath after an additional 15 minutes and allowed to warm to room
temperature while stirring for 4 hours. The reaction was quenched with 0.2
mL sat. NH4Cl and concentrated under reduced pressure. The
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NOE 13C NMR[14] and 1H NMR of the unpurified material before being
isolated by column chromatography, eluting with hexanes/ethyl acetate.
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Acknowledgements
MRH acknowledges support for a summer stipend funded by the
Howard Hughes Medical Institute to the College of Charleston as
part of their 2012 Undergraduate Science Education Competition
and the National Center for Research Resources (5 P20
RR016461) and the National Institute of General Medical
Sciences (8 P20 GM103499) from the NIH. JCH acknowledges
support for a summer stipend funded by the College of Charleston
School of Science and Math Dean’s Research Fund. The students
enrolled in Advanced Synthesis Lab 371 during the fall of 2017
are acknowledged for synthesizing the imines used in this paper.
The College of Charleston is acknowledged for additional
financial support. The NMR spectrometer at the College of
Charleston is supported by the National Science Foundation
under Grant No. 1429308.
((
Keywords: diastereoselectivity • boron • nucleophilic addition •
chiral auxiliaries
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