Asymmetric [4 + 2] cycloaddition synthesis of 4H-chromene derivatives facilitated by group-assisted-purification (GAP) chemistry
Date
2021
Journal Title
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Abstract
In this work, we present a strategy for the preparation of functionalized 4H-chromene derivatives via a Cs2CO3-catalyzed [4 + 2] cycloaddition of enantiopure chiral salicyl N-phosphonyl imines with allenoates. Fifteen examples were achieved in excellent yields and diastereoselectivity. The products were purified simply by washing the crude mixture with hexanes following the Group-Assisted Purification (GAP) chemistry/technology to bypass traditional separation methods. The absolute configuration was unambiguously determined by X-ray structure analysis.
Description
© 2021 The Author(s). Published by the Royal Society of Chemistry. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
Keywords
Group-Assisted-Purification (GAP) Chemistry, 4H-Chromenes
Citation
Rouh, H., Tang, Y., Zhang, S., Ali, A. I. M., Surowiec, K., Unruh, D., & Li, G. (2021). Asymmetric [4 + 2] cycloaddition synthesis of 4H-chromene derivatives facilitated by group-assisted-purification (GAP) chemistry. RSC Advances, 11(63), 39790-39796. https://doi.org/10.1039/D1RA08323F