Dimethylformamide → Benzoic acid, 3-methoxy-4-methyl-, methyl ester

HRID 371524

反応式

HRID 371524 の反応式
[OH:1][C:2]1[CH:3]=[C:4]([CH:8]=[CH:9][C:10]=1[CH3:11])[C:5](O)=[O:6].[C:12]([O-])([O-])=O.[K+].[K+].CI.CN([CH:23]=[O:24])C>O>[CH3:12][O:1][C:2]1[CH:3]=[C:4]([CH:8]=[CH:9][C:10]=1[CH3:11])[C:5]([O:24][CH3:23])=[O:6]

参加物

6

反応物 4

HCID 6228DimethylformamideHCID 6328Methyl iodideHCID 11430Potassium CarbonateHCID 685123-Hydroxy-4-methylbenzoic acid

生成物 1

HCID 591123Benzoic acid, 3-methoxy-4-methyl-, methyl ester

試薬・触媒・溶媒 1

HCID 962Water溶媒

実験手順

A mixture of 30 g (0.20 mol) of 3-hydroxy-4-methylbenzoic acid, 68.1 g (0.49 mol) of K2CO3, and 123 mL (1.98 mol) of MeI in 250 mL of DMF was heated at reflux for 19 h. After cooling to room temperature, the reaction mixture was diluted with 500 mL of water and extracted with Et2O (2×300 mL). The organic phase was washed with water and brine, dried (MgSO4), and concentrated to 37 g of orange oil: TLC (5% Et2O/hexane) Rf 0.13 (3-hydroxy-4-methylbenzoic acid), 0.63 (methyl 3-methoxy-4-methylbenzoate), and 0.72. The oil was chromatographed on 450 g of silica gel with 5% Et2O/hexane (100-mL fractions) to give 19.5 g of methyl 3-methoxy-4-methylbenzoate and 6.6 g of methyl 3-methoxy-4-methylbenzoate contaminated with the higher Rf material. The impure fraction was chromatographed on 250 g of silica gel to afford an additional 5.6 g of product. The total yield of white crystalline solid, mp 50°-51° C., was 25.1 g (72%). A sample from an earlier experiment was characterized: IR (film) 1700, 1400, 1290, 1270, 1100 cm-1 ; 1H NMR (CDCl3) δ 2.25 (s, 3, ArCH3), 3.85 and 3.88 (2 s, 6, CO2CH3ArOCH3), 7.2-7.9 (m, 3, ArH); MS calcd for C10H12O3 180.0786, found 180.0779.

後処理

  1. temperaturewas heated
  2. temperatureat reflux for 19 h
  3. extractionextracted with Et2O (2×300 mL)
  4. washThe organic phase was washed with water and brine
  5. dry with materialdried (MgSO4)
  6. concentrationconcentrated to 37 g of orange oil
  7. customThe oil was chromatographed on 450 g of silica gel with 5% Et2O/hexane (100-mL fractions)

出典と根拠

ORDレコード
ord-c52bacfe1f2549a090c91a6d3d7e2dbf
出典データセット
uspto-grants-1985_07
特許番号
US04532343

関連ノート

読み込み中…