Water → 2,4-Dimethoxypyrimidine-5-carbaldehyde

HRID 1707954

反応式

HRID 1707954 の反応式
CCCCCC.Br[C:8]1[C:9]([O:16][CH3:17])=[N:10][C:11]([O:14][CH3:15])=[N:12][CH:13]=1.[CH:18](OCC)=[O:19].O>CCOCC>[CH:18]([C:8]1[C:9]([O:16][CH3:17])=[N:10][C:11]([O:14][CH3:15])=[N:12][CH:13]=1)=[O:19]

参加物

6

反応物 4

HCID 962WaterHCID 8025Ethyl formateHCID 8058HexaneHCID 2557195-Bromo-2,4-dimethoxypyrimidine

生成物 1

HCID 5977822,4-Dimethoxypyrimidine-5-carbaldehyde

試薬・触媒・溶媒 1

HCID 3283Diethyl Ether溶媒

反応条件

温度
-70 °C

実験手順

A solution of 1.6M n-Buli in hexane (48 ml, 73.6 mmol) was added over 5 min. to a stirred suspension of 5-bromo-2,4-dimethoxypyrimidine (16 g; 72.9 mmol) in dry Et2O (240 ml) at -70° C. under an atmosphere of dry N2. Dry ethyl formate (28 g: 377 mmol) was added and the orange solution stirred at -70° C. for 1 h then allowed to warm slowly to ambient temperature. Water (400 ml) was added and the aqueous layer separated and extracted with Et2O (3×200 ml). The ether layer was combined with the extracts and dried over MgSO4, filtered and evaporated. The residue was purified by column chromatography by preloading in SiO2 and eluting with EtOAc-hexane (3:7, v/v). Product fractions were combined and evaporated to give fine white needles, yield 6.89 g, (56%). Mass spectrum m/z 169 (M+H)+Analysis, found: C, 50:1;H,4.5;N,16.9%;C7H8N2O3 requires C,50.00; H,4.79; N, 16.66%.

後処理

  1. temperatureto warm slowly to ambient temperature
  2. customthe aqueous layer separated
  3. extractionextracted with Et2O (3×200 ml)
  4. dry with materialdried over MgSO4
  5. filtrationfiltered
  6. customevaporated
  7. customThe residue was purified by column chromatography
  8. washeluting with EtOAc-hexane (3:7, v/v)
  9. customevaporated
  10. customto give fine white needles, yield 6.89 g, (56%)

出典と根拠

ORDレコード
ord-d44ba53f2f18452188175c5c1e01b82f
出典データセット
uspto-grants-1994_10
特許番号
US05356882

関連ノート

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