Trifluoroacetic acid → (+)-12-Oxocalanolide A

HRID 363831

反応式

HRID 363831 の反応式
[CH3:1][C:2]1([CH3:25])[O:7][C:6]2[C:8]3[C:13]([CH2:14][CH2:15][CH3:16])=CC(=O)O[C:9]=3[C:18]([C:21](=[O:24])[CH2:22][CH3:23])=[C:19]([OH:20])[C:5]=2[CH:4]=[CH:3]1.[CH2:26](OC(OCC)C)[CH3:27].F[C:35](F)(F)[C:36]([OH:38])=[O:37]>C(OCC)(=O)C>[CH3:16][CH2:15][CH2:14][C:13]1[C:8]2[C:6]3[O:7][C:2]([CH3:1])([CH3:25])[CH:3]=[CH:4][C:5]=3[C:19]3[O:20][C@H:26]([CH3:27])[C@@H:22]([CH3:23])[C:21](=[O:24])[C:18]=3[C:9]=2[O:38][C:36](=[O:37])[CH:35]=1

参加物

5

反応物 3

HCID 6422Trifluoroacetic acidHCID 7765AcetalHCID 54948815-Hydroxy-2,2-dimethyl-6-propionyl-10-propyl-2H,8H-pyrano[2,3-f]chromen-8-one

生成物 1

HCID 463613(+)-12-Oxocalanolide A収率 30%

試薬・触媒・溶媒 1

HCID 8857Ethyl Acetate溶媒

反応条件

温度
140 °C

実験手順

A solution containing chromene 4 (344 mg, 1.0 mmol), acetaldehyde diethylacetal (473 mg, 4.0 mmol), trifluoroacetic acid (1.5 mL, 19.4 mmol) and anhydrous pryidine (0.7 mL) was heated at 140° C. under N2. The reaction was monitored by TLC analysis. After 4 hours, the reaction mixture was cooled to room temperature, diluted with ehtyl acetate and washed several times with 10% aqueous NaHCO3 and brine. The organic layer was separated and dried over Na2SO4. The solvent was removed in vacuo and the crude product was purified by silica gel column chromatography eluting with ethyl acetate/hexane (2:3). Chromanone 7 (10,11-trans-dihydro-6,6,10,11-tetramethyl-4-propyl-2H,6H,12H-benzo[1,2-b:3,4-b':5,6-b"]-tripyran-2,12-dione) (110 mg, 30% yield) was obtained m.p. 176°-177° C. (Lit.5 130°-132° C.). 1H-NMR5 (CDCl3) δ 1.02 (3H, t, J=7.5 Hz, CH3); 1.21 (3H, d, J=6.8 Hz, CH3); 1.51 (3H, d, J=7.0 Hz, CH3); 1.55 (6H, 2s, 2 CH3); 1.63 (2H, sextet, J=7.0 Hz, CH2); 2.55 (1H, dq, J=6.9 Hz, J=11.0 Hz, H11); 2.88 (2H, t, J=7.6 Hz, CH2); 4.28 (1H, dq, J=6.3 Hz, J=11.0 Hz, H10); 5.60 (1H, d, J=9.9 Hz, H8); 6.04 (1H, s, H3); 6.65 (1H, d, J=11.8 Hz, H7); MS (CI): 369 (100, M+1).

後処理

  1. temperaturethe reaction mixture was cooled to room temperature
  2. washwashed several times with 10% aqueous NaHCO3 and brine
  3. customThe organic layer was separated
  4. dry with materialdried over Na2SO4
  5. customThe solvent was removed in vacuo
  6. customthe crude product was purified by silica gel column chromatography
  7. washeluting with ethyl acetate/hexane (2:3)

出典と根拠

ORDレコード
ord-0fc56c0ea8cc405aba48ae78758aac1b
出典データセット
uspto-grants-1999_02
特許番号
US05874591

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