Synthesis of 3-Trifluoromethyl-Substituted Benzo[f]chromene Derivatives in a One-Pot Reaction

Abstract

In the presence of 1,8-diazabicycolo[5.4.0]undec-7-ene (DBU) and concentrated H₂SO₄, 2-naphthol reacted smoothly with α,β-unsaturated trifluoromethyl ketones in CH₂Cl₂ at room temperature, affording the 3-trifluoromethyl-substituted benzo[f]chromene derivatives in good to excellent yields in a one-pot reaction.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource: Full experimental and spectral details].

GRAPHICAL ABSTRACT

Keywords:

• Benzo[f]chromene
• 2-naphthol
• one-pot reaction
• α,β-unsaturated trifluoromethyl ketone

ACKNOWLEDGMENT

This research was supported by the National Natural Science Foundation of China (Nos. 21032006 and 20172064), the QT Program, Shanghai Natural Science Council.

Notes

^a The reaction was carried out with 1a (0.15 mmol), 2a (0.1 mmol), and base (0.02 mmol) at room temperature in DCM (1.0 mL).

^b Yield of the isolated product after column chromatography on silica gel.

^a The reaction was carried out with 1a (0.15 mmol), 2a (0.1 mmol), and base (0.02 mmol) at room temperature in solvent (1.0 mL).

^b Isolated yield of the product after column chromatography on silica gel.

^a The reaction was carried out with 1 (0.15 mmol), 2 (0.1 mmol), and base (0.02 mmol) at room temperature in solvent (1.0 mL).

^b Isolated yield of the product after column chromatography on silica gel.