Three-component reactions of isochromenylium tetrafluoroborates via non-classical [4+2]-intermediates: mild one-step metal-free synthesis of functionalized dihydronaphthalenes and tetrahydronaphthalenes.
Two novel types of elegant three-component reactions of stable isochromenylium tetrafluoroborates (ICTBs) have been developed under mild metal-free conditions in this work. Mechanistically, these reactions are commonly initiated by a [4+2]-cycloaddition between the non-classical isochromenylium diene and the aldehyde-enol, and terminated by the following addition of weak nucleophiles, including nitriles or the second equivalent of aldehydes, in a one-pot fashion. The developed methodologies exhibit excellent chemoselectivity, regioselectivity, and diastereoselectivity, and provide a new convenient access to functionalized dihydronaphthalenes and tetrahydronaphthalenes.
State Key Laboratory of Bioorganic and Natural Products Chemistry, EISU Chemical Biology Division, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China.
Zhi-Long
ZL
Hu
Zhen-Yu
ZY
Yang
Shaozhong
S
Wang
Zhu-Jun
ZJ
Yao
D000447:Aldehydes / Q000737:chemistry*; D001881:Borates / Q000737:chemistry*; D003500:Cyclization; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D013237:Stereoisomerism; D013343:Styrenes / Q000737:chemistry*; D013764:Tetrahydronaphthalenes / Q000138:chemical synthesis* / Q000737:chemistry*
D000447:Aldehydes; D001881:Borates; D013343:Styrenes; D013764:Tetrahydronaphthalenes; C546493:isochromenylium tetrafluoroborate