Chemistry - A European Journal
10.1002/chem.201604503
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membered ring intermediate with diboronic acid, which
suppresses the formation of 1,2-addition intermediate (2s''). In
sharp contrast, although 8-hydroxyl-quinoline (2j) can form
another six-membered ring (2j'), this configuration does not
block the 1,2-addition site, back folding to coordinate with water
toward the positive result. As evidence, the intermediates 2s', 2j',
Keywords: hydrogen atom transfer • water • metal-free • N-
heterocycles • diboronic acid
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j'' were found in reaction mixtures monitored by HR-MS except
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Figure 3. Rationalization of Reaction Results
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0
was then heated to 80 C for 10 minutes until the complete consuming of
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(
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yield).
[7]
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We are grateful for financial support from the National Natural
Science Foundation of China (NSFC, Grant No. 21372118), the
Fundamental Research Funds for the Central Universities
(Grant No. KYTZ201604), the Foundation Research Project of
Jiangsu Province (The Natural Science Foundation No.
BK20141359) and “333 High Level Talent Project” of JiangSu
Province. Special thanks to Ms. Qing Sun (Xiamen University)
for theoretical calculations.
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