ChemicalBook CAS DataBase List Formononetin

Formononetin synthesis

5synthesis methods

Product Name:Formononetin
CAS Number:485-72-3
Molecular formula:C16H12O4
Molecular Weight:268.26

2632-13-5
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$5.00/25mg

95-01-2
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485-72-3
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$5.00/250mg

Yield:485-72-3 80%

Reaction Conditions:

Stage #1:2-Bromo-4'-methoxyacetophenone with thiamine hydrochloride in ethanol at 20; for 0.25 h;Green chemistry;
Stage #2:2,4-Dihydroxybenzaldehyde in ethanol at 20; for 1.5 h;Green chemistry;

Steps:

Experimental
General procedure: To prepare catalyst, 0.21 g of thiamine hydrochloride (0.6 mmol) was dissolved in 0.64 mL of water and added 2.4 mLof 95% ethanol (water : 95% ethanol = ~1:4). The solution was cooled in an ice bath, then added 0.40 mL of 3 M NaOH(1.2 mmol) dropwise with stirring in a manner such that thetemperature remained below 20 °C. Intense yellow coloured solution changed to pale yellow solution of thiamine (thiazolium ion)/N-heterocyclic carbene (Scheme 1).⁴⁷ In a 25-mL round bottom flask, a mixture of phenacylbromide 1 (2.5 mmol, 0.5 g in case of 1a) and thiamine (0.6 mmol, 25 mol %) in ethanol (4 mL) was stirred at room temperature for 15 min. Then, salicylaldehyde 2 (2.5 mmol, 0.26 mL in case of 2a) was added slowly and the mixture was stirred at room temperature until the reaction was completed (as monitored by TLC) (Table 3) . The reaction mixture was then poured into 20 mL of distilled water and extracted with ethyl acetate (3 × 10 mL). The organic layer was dried over anhydrous Na₂SO₄ and the solvent was removed under reduced pressure. The resulting product isoflavone 3 was further purified either by recrystallizationor by column chromatography (Ethyl acetate:Hexane, 1:4v/v). All compounds were characterized by their mp and ¹HNMR, ¹³CNMR and mass spectral data.

References:

Mishra, Priya;Singh, Sarita;Ankit, Preyas;Fatma, Shahin;Singh, Divya;Singh, Jagdamba [Bulletin of the Korean Chemical Society,2013,vol. 34,# 4,p. 1070 - 1076]

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