Reaction #531809

Reaction equation

4-Benzyloxy-2,5-dimethoxyphenylboronic acid

5-Acetyl-2-trifluoromethanesulfonyloxy-benzoic acid methyl ester

5-Acetyl-2-trifluoromethanesulfonyloxybenzoic acid methyl ester

K2CO3

water

→

7b

Yield 115.6%

4-Acetyl-4′-benzyloxy-2′-methoxybiphenyl-2-carboxylic acid methyl ester

Yield 115.6%

Solvents

brine

ethyl acetate

Conditions

Workup

1. 1
   Otherthe flask was flushed with Ar
2. 2
   workup.ADDITIONAbsolute ethanol (83 mL) and DME (94 mL) were added
3. 3
   Temperaturethe reaction mixture refluxed for 4 h
4. 4
   TemperatureAfter cooling
5. 5
   WashThe organic layer was washed with brine (2×50 mL)
6. 6
   Extractionthe combined aqueous fraction was back extracted with ethyl acetate
7. 7
   OtherThe combined organic fraction was dried
8. 8
   Concentrationconcentrated
9. 9
   Otherrecrystallized from ethyl acetate/hexanes

Procedure

4-Benzyloxy-2,5-dimethoxyphenylboronic acid 5b (4.15 g, 14.4 mmol), 5-Acetyl-2-trifluoromethanesulfonyloxy-benzoic acid methyl ester 6 (4.69 g, 14.4 mmol) and K2CO3 (3.98 g, 28.8 mmol) were added and the flask was flushed with Ar. Absolute ethanol (83 mL) and DME (94 mL) were added followed by Pd (PPh3)4 (0.87 g, 0.785 mmol) and the reaction mixture refluxed for 4 h. After cooling, water (100 ml), ethyl acetate (100 mL) and brine (50 mL) were added. The organic layer was washed with brine (2×50 mL) and the combined aqueous fraction was back extracted with ethyl acetate. The combined organic fraction was dried, concentrated and recrystallized from ethyl acetate/hexanes to give 6.5 g (99%) of 7b as a yellow solid. 1H-NMR (400 MHz, CDCl3) dH 2.65 (3H, s, COCH3), 3.58 (3H, s, OCH3), 3.68 (3H, s, OCH3), 3.88 (3H, s, OCH3), 5.21 (21H, s, CH2Ph), 6.55 (1H, s, ArH), 6.86 (1H, s, ArH), 7.30-7.48 (6H, m, ArH+CH2Ph), 8.10 (1H, d, ArH),8.37(1H,s,ArH),

Source