G Model
CCLET 2967 1–5
J.-J. Li, X.-X. Gui / Chinese Chemical Letters xxx (2014) xxx–xxx
5
Scheme 3. Proposed mechanism for the reaction of purines and vinyl ethers.
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4. Conclusion
Lett. 14 (2004) 3357–3360.
175
139
140
141
142
143
144
145
146
147
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In summary, we have developed an alternative route to N-9-
alkoxyalkylated nucleobases through highly regioselective alkox-
yalkylation of purines with vinyl ethers catalyzed by
characterized by high regioselectivity, employment of cost-
effective catalyst, mild conditions. Besides, the -ProT catalyzed
addition reaction shows general tolerance to variety of
functionalities, such as Cl and Boc, making this method quite
attractive. Further application of this methodology to synthesize
more promising N-9-alkoxyalkylated purine nucleosides is now
underway in our laboratory.
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tion of N-heterocycles to a,b-unsaturated ketones and imides, Angew. Chem. Int. 177
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178
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180
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L
lective aza-Michael addition of purine bases to a,b-unsaturated ketones, Adv. 182
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Acknowledgments
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192
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triflate (PFPAT): an efficient, practical, and cost-effective catalyst for esterifica- 194
tion, thioesterification, transesterification, and macrolactone formation, Green 195
150 Q2
151
152
We are grateful to the Natural Science Foundation of Zhejiang
Province (No. LY13B020015) and Zhejiang Key Innovation Team of
Green Pharmaceutical Technology (No. 2012R10043-07) for
financial support.
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Please cite this article in press as: J.-J. Li, X.-X. Gui,
L-ProT catalyzed highly regioselective N-alkoxyalkylation of purine rings with vinyl