10.1002/adsc.201900287
Advanced Synthesis & Catalysis
successful conversion. We also demonstrated the
continuous flow synthesis of multiflorol.
62, 994; i) D. R. Boyd, E. R. Marle, J. Chem. Soc., Trans.
1914,105, 2117-2139.
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Experimental Section
General Procedure for the Hydroxyethylation Reaction.
To a 5 mL round-bottom flask was sequentially added
ethylene carbonate (97 mg, 1.1 mmol, 1.1 equiv), a
phenolic substrate (1.0 mmol), TBAF·3H2O (3.2 mg, 0.01
mmol), and DMF (0.1 mL). The resulting mixture was
brought to 170 °C (aluminium heating block) and stirred
under N2 atmosphere. After the phenol was completely
consumed as judged by thin layer chromatography (TLC),
the reaction was allowed to cool to room temperature. The
crude mixture was directly purified by flash column
chromatography over silica gel to give the desired
ethoxylated product.
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Acknowledgements
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We thank the Young Scholar Fellowship Program by the Ministry
of Science and Technology in Taiwan (MOST107-2636-M-009-
003 and MOST108-2636-M-009-003) for financial support of this
work. We also appreciate valuable comments from the referees.
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