ChemicalBook CAS DataBase List 2,3-DIFLUORO-6-METHOXYBENZALDEHYDE

2,3-DIFLUORO-6-METHOXYBENZALDEHYDE synthesis

4synthesis methods

Product Name:2,3-DIFLUORO-6-METHOXYBENZALDEHYDE
CAS Number:187543-87-9
Molecular formula:C8H6F2O2
Molecular Weight:172.13

758-16-7
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$21.21/5gm:

115144-40-6
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$9.00/5g

187543-87-9
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$25.00/250mg

Yield:187543-87-9 95%

Reaction Conditions:

Stage #1: 1,2-difluoro-4-methoxy-benzenewith lithium diisopropyl amide in tetrahydrofuran at -75; for 1 h;
Stage #2: N,N-dimethylthioformamide in tetrahydrofuran;water;acetic acid at -70 - 10; for 0.166667 h;

Steps:

2,3-Difluoro-6-methoxybenzaldehyde

2, 3-DIFLUORO-6-METHOXYBENZALDEHYDE A solution of lithium diisopropylamide, 2M in THF/N-HEPTANE (171 mL, 341 mmol) was further diluted with dry THF (250 ML) and cooled under nitrogen TO-75C. 3,4- Difluoroanisole (46.8 g, 325 mmol) in dry THF (100 ML) was added dropwise and the mixture stirred at-75C for LH. Dry N, N dimethylformamide (27.6 ML, 358 mmol) was added dropwise and the mixture stirred for 10 mins AT-70C. Acetic acid (30 ML) and water (400 ML) were added, warming the temperature to 10C. Extracted into diethyl ether (2 x 300 mL). Combined extracts were washed with water (250 mL), aqueous hydrochloric acid (0.2 N, 400 mL) and brine (2 x 250 mL), dried (MgSO4) and the solvent evaporated in vacuo to give a RED/ORANGE oil which crystallised. Purification was by recrystallisation from diethyl ETHER/PETROLEUM ether 40-60 to give (53. 0g, 95%) of solid; ON (300 MHz, CDC13) 10.40 (1H, s, CHO), 7.37 (1H, q, ArH), 6.71 (1H, m, ArH), and 3.93 (3H, s OCH3).

References:

WO2004/43903,2004,A1 Location in patent:Page 40 - 41

4394-85-8 Synthesis