4
Tetrahedron
explain the experimental results. Investigations concerning the
biological activity of the obtained products are currently ongoing.
Acknowledgments
This work was partly supported by the National Nature
Science Foundation of China (Nos. 21302124, 21302127,
21232004), Shanghai Chenguang Project (No.14CG11), and
Science and Technology Commission of Shanghai Municipality
(Nos. 14XD1402300 and 15Z111220016). We thank the
Instrumental Analysis Center of SJTU.
Scheme 3. Reaction results with 1 equiv of NFSI.
References and notes
When only 1.0 equivalent of NFSI was used, the amounts of
byproducts increased (Scheme 3). Two major byproducts were
1.
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isolated and identified: isoindolinone
4
produced by
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aza-Wacker-type reaction.[12g] Based on this information, we have
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Scheme 4. Proposed reaction mechanism.
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In summary, an efficient diamination of ortho-olefinic N-
methoxybenzamide with NFSI using a palladium catalyst was
developed, giving the amine-functionalized isoindolinones in
good yields. The reactions could be carried out under relatively
mild conditions, allowing for the synthesis of a variety of
isoindolinones. A plausible mechanism has been proposed to