m-Chloroperbenzoic acid → 2-[(4-Isopropoxy-3-methoxy-phenyl)ethynyl]-5-isopropoxy-4-methoxyphenol

HRID 1244783Notes

Reaction equation

HRID 1244783 reaction equation
ClC1C=C(C=CC=1)C(OO)=[O:6].[CH:12]([O:15][C:16]1[CH:21]=[CH:20][C:19]([C:22]#[C:23][C:24]2[CH:31]=[C:30]([O:32][CH3:33])[C:29]([O:34][CH:35]([CH3:37])[CH3:36])=[CH:28][C:25]=2C=O)=[CH:18][C:17]=1[O:38][CH3:39])([CH3:14])[CH3:13]>C(Cl)Cl>[CH:12]([O:15][C:16]1[CH:21]=[CH:20][C:19]([C:22]#[C:23][C:24]2[CH:31]=[C:30]([O:32][CH3:33])[C:29]([O:34][CH:35]([CH3:37])[CH3:36])=[CH:28][C:25]=2[OH:6])=[CH:18][C:17]=1[O:38][CH3:39])([CH3:13])[CH3:14]

Participants

4

Conditions

Temperature
0 °C

Procedure

m-Chloroperoxybenzoic acid [1.2 g, ALDRICH, 50% (remainder 3-chlorobenzoic acid and water), ca. 7.0 mmol] was added in portions over 0.25 h to a magnetically stirred mixture of 2-[(4-isopropoxy-3-methoxy-phenyl)ethynyl]-5-isopropoxy-4-methoxybenzaldehyde (2.20 g, 5.75 mmol) and KHCO3 (1.73 g, 17.3 mmol) in CH2Cl2 (50 mL) maintained at 0° C. (ice-bath). The resulting slurry was stirred for a further 1 h between 0° C. and 18° C. then filtered through Celite® and the solids thus retained rinsed with CH2Cl2 (1×50 mL). The combined filtrates were concentrated under reduced pressure and the residue treated with NH3 (30 ml of a saturated methanolic solution). After 1 h at 18° C. the reaction mixture was concentrated under reduced pressure and the residue redissolved in CH2Cl2 (200 mL) then concentrated on to silica gel (8 g, 400–200 mesh). The resulting powder was loaded on top of a column of silica (40–10 mesh TLC grade, 10 cm wide×5 cm long) and eluted with 2:1, 1:1 and 1:2 hexane/CH2Cl2 then neat CH2Cl2 (250 ml of each). The appropriate fractions (Rf 0.3 in 1:2 hexane/CH2Cl2) were concentrated under reduced pressure to give the title compound (1.97 g, 92%) as white crystalline masses, mp 130–1° C. IR (KBr disc, cm−1) 3404, 2981, 2935, 1620, 1573, 1513, 1467, 1450, 1418, 1383, 1373, 1330, 1269, 1240, 1214, 1166, 1135, 1113, 951. 1H NMR(300 MHz CDCl3) δ 7.03 (dd, J=1.8, 8.4 Hz, 1H), 7.00 (d, J=2.1 Hz, 1H), 6.87 (s, 1H), 6.81 (d, J=8.4 Hz, 1H), 6.53 (s, 1H), 5.81 (s, 1H), 4.52 (septet, J=6.0 Hz, 2H), 3.82 (s, 3H), 3.78 (s, 3H), 1.35 (d, J=6.0 Hz, 12H). 13C NMR+APT (75.5 MHz, CDCl3) δ 151.8 (C), 149.7 (C), 149.3 (C) 147.8 (C), 143.6 (C), 124.6 (CH), 115.0 (C), 114.7 (CH), 114.6 (CH), 114.3 (CH), 102.0 (CH), 100.1 (C), 94.7 (C), 82.2 (C), 71.1 (CH), 71.0 (CH), 56.4 (CH3), 55.7 (CH3), 21.9 (CH3), 21.8 (CH3). MS (70 eV) m/z (%): 370 (M+•), 355 (2, M+•-CH3), 328 (18, M+•-CH(CH3)2], 327 (20, M+•CH2CHCH3), 286 (100, M+•-2×CH2CHCH3), 271 (42, M+•-2×CH2CHCH3—CH3). Anal. Calcd for C22H26O5 C, 71.33; H, 7.07. Found: C, 70.91; H. 7.24.

Workup

  1. filtrationthen filtered through Celite®
  2. washthe solids thus retained rinsed with CH2Cl2 (1×50 mL)
  3. concentrationThe combined filtrates were concentrated under reduced pressure
  4. additionthe residue treated with NH3 (30 ml of a saturated methanolic solution)
  5. concentrationAfter 1 h at 18° C. the reaction mixture was concentrated under reduced pressure
  6. dissolutionthe residue redissolved in CH2Cl2 (200 mL)
  7. concentrationthen concentrated on to silica gel (8 g, 400–200 mesh)
  8. washeluted with 2:1, 1:1 and 1:2 hexane/CH2Cl2
  9. concentrationThe appropriate fractions (Rf 0.3 in 1:2 hexane/CH2Cl2) were concentrated under reduced pressure

Sources & evidence

ORD record
ord-09f3b47ab1124f568845a5e3706330c2
Source dataset
uspto-grants-2006_10
Patent number
US07122673B2

Reaction notes

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