Synthesis 2018; 50(06): 1307-1314
DOI: 10.1055/s-0036-1591724
paper
© Georg Thieme Verlag Stuttgart · New York

Brønsted Acid Catalyzed Domino 1,6-Addition/Intramolecular Cyclization­ Reactions: Diastereoselective Synthesis of Dihydro­coumarin Frameworks

Zheng Cao
,
Gui-Xiang Zhou
,
Chun Ma
,
Kang Jiang
,
Guang-Jian Mei*
We much appreciate the financial support from NSFC (21702077), the Natural Science Foundation of Jiangsu Province (BK20170227), PAPD, TAPP and the Undergraduate Student Project of Jiangsu Province.
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Publication History

Received: 19 September 2017

Accepted after revision: 20 October 2017

Publication Date:
21 November 2017 (online)


Abstract

An efficient domino 1,6-addition/intramolecular cyclization reaction between para-quinone methides (p-QMs) and azlactones under Brønsted acid catalysis was established. A series of highly functionalized dihydrocoumarins were constructed in good to excellent yields (up to 96%) with excellent diastereoselectivities (all >20:1 d.r.). In this process, the Brønsted acid plays a crucial role not only in activating the two substrates, but also in controlling the diastereoselectivity of the reaction via hydrogen-bonding interactions. In addition, this protocol demonstrates the great practicability of utilizing p-QMs in domino reactions.

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