HCID 131720242, compound → HCID 22878252, compound

HRID 1489209Notes

Reaction equation

HRID 1489209 reaction equation
C=C1CCCC(C)(C)[C@H]1CC1C=C(OC)C(Br)=C(O[SiH](C)C)C=1C(C)(C)C.[CH2:28]=[C:29]1[C@@H:34]([OH:35])[CH2:33][C@H:32](Br)[C:31]([CH3:38])([CH3:37])[C@H:30]1[CH2:39][C:40]1[CH:45]=[C:44]([O:46][CH3:47])[C:43]([Br:48])=[CH:42][C:41]=1[O:49]C(=O)C.[SiH3]C1C=CC=CC=1O>>[OH:35][C@@H:34]1[CH2:33][CH2:32][C:31]([CH3:37])([CH3:38])[C@@H:30]([CH2:39][C:40]2[CH:45]=[C:44]([O:46][CH3:47])[C:43]([Br:48])=[CH:42][C:41]=2[OH:49])[C:29]1=[CH2:28]

Participants

4

Reactant 3

HCID 131720242HCID 131720242, compoundHCID 131720243HCID 131720243, compoundHCID 131720244HCID 131720244, compound

Product 1

HCID 22878252HCID 22878252, compound

Procedure

This set of diastereomeric alcohols was prepared from (2R)-1-methylidene-2-[2'-(tert-butyl)dimethylsilyloxy-4'-bromo-5'-methoxyphenyl]methyl-3,3-dimethylcyclohexane (48) (0.750 g, 1.66 mmol) in the manner previously described for the synthesis of alcohol 54, affording 741 mg (95%) of an inseparable 1:1 mixture of diastereomeric allylic alcohols. A portion (40 mg, 0.085 mmol) of this diastereomeric mixture was subjected to deprotection of the silylphenol in the usual manner, yielding mixture of free phenols, separable by flash column chromatography (silica gel, hexanes lethyl acetate, gradient elution), to give 14.0 mg (46%) of the less polar 1R,3R diastereomer (56), along with 13.0 mg (43%) of the more polar 1S,3R diastereomer (57) as white solids. Data for 56: 1H NMR (400MHz, CDCl3) δ0.93 and 1.12 (2s, 2×3H, geminal-CH3 's), 1.70 (m, 2H, 1-H), 1.94 (m, 3H, 6,3-H), 2.65 and 3.00 (d of ABq, 2H, JAB =14.0 Hz, JA =3.1 Hz, JB =14.0 Hz, benzylic-CH2) 3.84 (s, 3H, OCH3), 4.37 (br s, 1H, 5-H), 4.39 and 4.92 (2s, 2×1H, methylidene-CH2), 6.58 (s, 1H, 6'-H), 7.02 ppm (s, 1H, 3'-H). Data for 57: 1H NMR (400 MHz, CDCl3) δ1.00 and 1.02 (2s, 2×3H, geminal-CH3 's), 2.45 (dd, 1H, J=11.5, 3.2 Hz, 3-H), 2.70 and 2.88 (d of ABq, 2H, JAB =14.1 Hz, JA =13.1 Hz, JB =4.2 Hz, benzylic-CH2) 3.80 (s, 3H, OCH3), 4.40 (br dd, 1H, J13 11.5, 4.5 Hz, 5-H), 4.47 and 4.86 (2s, 2×1H, methylidene-CH2). 6.61 (s, 1H, 6'-H), 7.94 ppm (s, 1H, 3'-H). [Compound 56 is hereinafter also referred to as COMPOUND "R" or 120243]

Workup

  1. customaffording
  2. customyielding
  3. washseparable by flash column chromatography (silica gel, hexanes lethyl acetate, gradient elution)

Sources & evidence

ORD record
ord-c77719c2d54c4c37804b93bb8ffe5726
Source dataset
uspto-grants-1997_10
Patent number
US05677336

Reaction notes

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