ChemicalBook CAS DataBase List 2'-METHYLPHENACYL BROMIDE

2'-METHYLPHENACYL BROMIDE synthesis

5synthesis methods

Product Name:2'-METHYLPHENACYL BROMIDE
CAS Number:51012-65-8
Molecular formula:C9H9BrO
Molecular Weight:213.07

933-88-0

18107-18-1

51012-65-8

Example 6 Preparation of 2-bromo-1-o-tolylacetophenone (I15): 2-methylbenzoyl chloride (169 μL, 1.29 mmol) was dissolved in anhydrous acetonitrile (5 mL) under nitrogen protection and cooled to 0°C. Subsequently, (diazomethyl)-trimethylsilane (1.94 mL, 3.88 mmol, 2 M hexane solution) was slowly added. The reaction mixture was stirred at room temperature for 15 h. The reaction mixture was again cooled to 0 °C and 48% hydrobromic acid (512 μL, 4.53 mmol) was slowly added. The reaction mixture was continued to be stirred at room temperature for 3 hours. After completion of the reaction, the organic layer was separated by adding ethyl acetate (EtOAc) and water for extraction. The aqueous phase was neutralized with 1 M sodium hydroxide (NaOH) and extracted again with ethyl acetate. The organic layers were combined, dried with anhydrous sodium sulfate (Na2SO4), filtered and concentrated under reduced pressure to afford 2-bromo-1-o-toluene ethanone (250 mg, 91% yield). The intermediate could be used for subsequent reactions without further purification.1H NMR (300 MHz, DMSO-d6) δ ppm: 7.82-7.91 (m, 1H), 7.45-7.52 (m, 1H), 7.25-7.40 (m, 2H), 4.86 (s, 2H), 2.41 (s, 3H).

933-88-0 Synthesis

933-88-0
350 suppliers
$10.00/1g

18107-18-1
209 suppliers
$33.00/5g

51012-65-8
124 suppliers
$26.00/200mg

Yield: 91%

Reaction Conditions:

with hydrogen bromide in hexane;water;ethyl acetate;acetonitrile

Steps:

6 Preparation of 2-bromo-1-o-tolylethanone (I15)
Example 6 Preparation of 2-bromo-1-o-tolylethanone (I15) To a solution of 2-methylbenzoyl chloride (169 μl, 1.29 mmol) in dry acetonitrile (5 ml) and cooled at 0° C., under nitrogen atmosphere, was added (diazomethyl)-trimethylsilane (1.94 ml, 3.88 mmol, 2M in hexane). The reaction was stirred at room temperature for 15 hours, then it was cooled at 0° C. and 48% HBr (512 μl, 4.53 mmol) was slowly added. The reaction was stirred at room temperature for 3 hours. EtOAc and water were added, the organic layer was separated and the aqueous phase was neutralized with 1M NaOH and extracted with EtOAc. The combined organic layers were dried over Na₂SO₄, filtered and evaporated to dryness to obtain 2-bromo-1-o-tolylethanone (250 mg, 91% yield). This intermediate was used in the next step without any further purification. ¹H NMR (300 MHz, DMSO-d₆) δ ppm 7.82-7.91 (m, 1H), 7.45-7.52 (m, 1H), 7.25-7.40 (m, 2H), 4.86 (s, 2H), 2.41 (s, 3H).

References:

Chiesi Farmaceutici S.p.A. US2011/311458, 2011, A1

611-15-4 Synthesis