Brønsted Acid-Catalyzed Formal (3+3)-Annulation of Propargylic (Aza)-para-Quinone Methides with 4-Hydroxycoumarins and 1,3-Dicarbonyl Compounds

An efficient approach for the synthesis of chromene derivatives from vinyl o-quinone methides was established via a Brønsted acid catalyzed electrocyclization. By using this methodology, a series of structurally diversified chromenes was synthesized in a highly atom-economic and environmentally benign manner with generally good to excellent yields (up to 98% yield). This reaction will not only provide an efficient method for the construction of chromene scaffolds, but also enrich the research area of o-quinone methides.

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Brønsted Acid Catalyzed Amination of 1,3-Dicarbonyl Compounds by Iminoiodanes

Synlett ◽

10.1055/s-0033-1340108 ◽

2013 ◽

Vol 25 (02) ◽

pp. 201-204 ◽

Cited By ~ 1

Author(s):

Philip Chan ◽

Ciputra Tejo ◽

Hui Yeo

Keyword(s):

Bronsted Acid ◽

Brønsted Acid ◽

Dicarbonyl Compounds ◽

Brönsted Acid ◽

Acid Catalyzed

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Highly regioselective synthesis of 2,3-disubstituted 2 H -1-benzopyrans: Brønsted acid catalyzed [4+2] cycloaddition reaction with a variety of arylalkynes via ortho -quinone methides

Tetrahedron ◽

10.1016/j.tet.2017.09.045 ◽

2017 ◽

Vol 73 (45) ◽

pp. 6456-6464 ◽

Cited By ~ 15

Author(s):

Kenta Tanaka ◽

Mayumi Sukekawa ◽

Yosuke Shigematsu ◽

Yujiro Hoshino ◽

Kiyoshi Honda

Keyword(s):

Cycloaddition Reaction ◽

Regioselective Synthesis ◽

Bronsted Acid ◽

Brønsted Acid ◽

Quinone Methides ◽

Brönsted Acid ◽

Acid Catalyzed

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Brønsted Acid-Catalyzed Cycloisomerization of But-2-yne-1,4-diols with or without 1,3-Dicarbonyl Compounds to Tri- and Tetrasubstituted Furans

The Journal of Organic Chemistry ◽

10.1021/jo301093f ◽

2012 ◽

Vol 77 (16) ◽

pp. 6937-6947 ◽

Cited By ~ 31

Author(s):

Srinivasa Reddy Mothe ◽

Sherman Jun Liang Lauw ◽

Prasath Kothandaraman ◽

Philip Wai Hong Chan

Keyword(s):

Bronsted Acid ◽

Brønsted Acid ◽

Dicarbonyl Compounds ◽

Brönsted Acid ◽

Acid Catalyzed

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

Synthesis ◽

10.1055/s-0036-1591724 ◽

2017 ◽

Vol 50 (06) ◽

pp. 1307-1314 ◽

Cited By ~ 3

Author(s):

Guang-Jian Mei ◽

Zheng Cao ◽

Gui-Xiang Zhou ◽

Chun Ma ◽

Kang Jiang

Keyword(s):

Hydrogen Bonding ◽

Crucial Role ◽

Acid Catalysis ◽

Bronsted Acid ◽

Brønsted Acid ◽

Diastereoselective Synthesis ◽

Quinone Methides ◽

Hydrogen Bonding Interactions ◽

Brönsted Acid ◽

Acid Catalyzed

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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