10.1002/adsc.201701221
Advanced Synthesis & Catalysis
References
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Scheme 3. Proposed mechanism.
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Conclusion
We have developed an practical Zn(OAc)2-catalyzed
reductive amination of various carbonyl compounds
with DMF. This reaction utilized the most common
and cheap Zn(OAc)2·2H2O as catalyst, widely used
DMF as a slow and steady source of Me2N and
reductant to avoid pressure-proof reactor and
operation. This reaction shows good functionality
tolerance and broad substrate scope including
aromatic/aliphatic aldehyde, aliphatic ketone, to react
with N-di-substituted, mono-substituted and un-
substituted formamide, in up to 98% isolated yield. At
the same time, the reaction is so clean that no column
chromatograph is required and simple extraction-
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Experimental Section
A general experimental procedure is described as [6] For recent report on noble metal catalyzed
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An oven-dried reaction vessel was charged with 2-
naphthaldehyde (1a, 0.2 mmol, 1 equiv), zinc acetate
dihydrate (0.02 mmol, 10 mol %), H2O (5.5 equiv),
N,N-dimethylformamide (2a, 0.5 mL) under air. The
vessel was sealed and heated at 150 °C (oil bath
temperature) for 24 h. After cooling down, 10 mL
brine was added in, followed by extractions with ether
(3x10 mL). The organic layer was combined, washed
with brine (2x10 mL), dried with anhydrous sodium
sulfate, filtered and concentrated in vacuo to give
N,N-dimethyl-1-(naphthalen-2-yl)methanamine (3a, [7 For recent report on noble metal catalyzed transferring
35.9 mg) in 97% yield.
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Acknowledgements
This work was supported by the National Natural Science
Foundation of China (21772168), Opening Fund of Beijing
National Laboratory for Molecular Sciences, Xiangtan
University “Academic Leader Program” (11QDZ20), Hunan
Provincial Natural Science Foundation (2016JJ2122), Key
Foundation of Education Bureau of Hunan Province
(17A208) and Hunan 2011 Collaborative Innovation Centre
of Chemical Engineering & Technology with Environmental
Benignity and Effective Resource Utilization.
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see: a) M. Rueping, E. Sugiono, F. R. Schoepke, Synlett
2010, 852; b) C. Zhu, K. Saito, M. Yamanaka, T.
Akiyama, Acc. Chem. Res. 2015, 48, 388; c) A. M. F.
Phillips, A. J. L. Pombeiro, Org. Biomol. Chem. 2017,
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The authors declare no competing financial interest.
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