1,4-Dipolar Cycloaddition Reactions in Ionic Liquids: A Facile Synthesis of 9aH,15H-[1]Benzopyrano[3′,2′: 3,4]pyrido[2,1-a]isoquinolines (=9aH,15H-Benzo[a][1]benzopyrano[2,3-h]quinolizines)

Authors

  • Basi V. Subba Reddy,

    Corresponding author
    1. Organic Chemistry Division I, Indian Institute of Chemical Technology, Hyderabad-500 007, India, (fax: +91-40-27160512)
    • Organic Chemistry Division I, Indian Institute of Chemical Technology, Hyderabad-500 007, India, (fax: +91-40-27160512)
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  • Nagendra Nath Yadav,

    1. Organic Chemistry Division I, Indian Institute of Chemical Technology, Hyderabad-500 007, India, (fax: +91-40-27160512)
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  • Nikhil Srivastava,

    1. Organic Chemistry Division I, Indian Institute of Chemical Technology, Hyderabad-500 007, India, (fax: +91-40-27160512)
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  • Jhillu S. Yadav,

    1. Organic Chemistry Division I, Indian Institute of Chemical Technology, Hyderabad-500 007, India, (fax: +91-40-27160512)
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  • Balasubramanian Sridhar

    1. Centre for X-Ray Crystallography, Indian Institute of Chemical Technology, Hyderabad-500 007, India
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Abstract

Ionic liquids were found to be a suitable reaction medium for 1,4-dipolar cycloaddition reactions of an isoquinoline, an activated alkyne, and a 4-oxo-4H-1-benzopyran-3-carboxaldehyde at room temperature to afford [1]benzopyrano-pyrido-isoquinoline (=9aH,15H-benzo[a][1]benzopyrano[2,3-h]quinolizine) derivatives selectively in good yields. The ionic liquid can be recovered and recycled in further runs without loss of activity.

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