Cross-Coupling of Amide and Amide Derivatives to Umbelliferone Nonaflates: Synthesis of Coumarin Derivatives and Fluorescent Materials
2020
Hickey, Shane M. | Nitschke, Samuel O. | Sweetman, Martin J. | Sumby, Christopher J. | Brooks, Douglas A. | Plush, Sally E. | Ashton, Trent D.
The Buchwald–Hartwig cross-coupling reaction between 4-methylumbelliferone-derived nonaflates with amides, carbamates, and sulfonamides is described. A wide variety of N-substituted 7-amino coumarin analogues was prepared in good to excellent yields. The photophysical properties of aqueous-soluble derivatives were determined, and they displayed auxochrome-based variations. Gram-scale synthesis provided an acrylamide analogue, which was used to fabricate a fluorescent poly(2-hydroxylethyl methacrylate) (pHEMA) hydrogel that was resistant to leaching in ultrapure H₂O. We envisage that our reported protocol to access 7-amino-4-methylcoumarin derivatives will find use toward the development of new fluorescent coumarin-based probes by researchers in the field.
显示更多 [+] 显示较少 [-]