Hydrochloric Acid → 4-Benzyloxy-6-[2-(3,4-dibenzyloxyphenyl)-2-hydroxyethyl]-2H-pyran-2-one

HRID 2910

Reaction equation

HRID 2910 reaction equation
C(NC(C)C)(C)C.C([Li])CCC.[CH2:13]([O:20][C:21]1[CH:26]=[C:25]([CH3:27])[O:24][C:23](=[O:28])[CH:22]=1)[C:14]1[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=1.[CH2:29]([O:36][C:37]1[CH:38]=[C:39]([CH:42]=[CH:43][C:44]=1[O:45][CH2:46][C:47]1[CH:52]=[CH:51][CH:50]=[CH:49][CH:48]=1)[CH:40]=[O:41])[C:30]1[CH:35]=[CH:34][CH:33]=[CH:32][CH:31]=1.[Cl-].[NH4+].Cl>O1CCCC1>[CH2:13]([O:20][C:21]1[CH:26]=[C:25]([CH2:27][CH:40]([C:39]2[CH:42]=[CH:43][C:44]([O:45][CH2:46][C:47]3[CH:52]=[CH:51][CH:50]=[CH:49][CH:48]=3)=[C:37]([O:36][CH2:29][C:30]3[CH:35]=[CH:34][CH:33]=[CH:32][CH:31]=3)[CH:38]=2)[OH:41])[O:24][C:23](=[O:28])[CH:22]=1)[C:14]1[CH:15]=[CH:16][CH:17]=[CH:18][CH:19]=1

Participants

8

Reactant 6

HCID 313Hydrochloric AcidHCID 7912DiisopropylamineHCID 25517Ammonium ChlorideHCID 795263,4-Bis(benzyloxy)benzaldehydeHCID 27844494-Benzyloxy-6-methyl-2H-pyran-2-oneHCID 178418339Butyllithium

Product 1

HCID 196880744-Benzyloxy-6-[2-(3,4-dibenzyloxyphenyl)-2-hydroxyethyl]-2H-pyran-2-oneYield 68%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent3×

Conditions

Temperature
-78 °C

Procedure

A solution of 10.1 g (14.0 ml, 100 mmol) diisopropylamine in 150 ml tetrahydrofuran was mixed under nitrogen at -78° C. with 41.0 ml (95 mmol) butyllithium (2.3M in n-hexane). It was allowed to reach 0° C. for a short time and immediately cooled again to -78° C. After a dropwise addition of a solution of 19.0 g (88 mmol) 4-benzyloxy-6-methyl-2H-pyran-2-one (V) in 100 ml anhydrous tetrahydrofuran it was stirred for a further 45 min. at -78° C. and subsequently a solution of 12.8 g (40 mmol) 3,4-dibenzyloxy-benzaldehyde (IV) in 150 ml anhydrous tetrahydro-furan was added dropwise. The internal temperature was gradually increased to -30° C. and it was admixed with an excess of saturated ammonium chloride solution. After acidifying with 6n HCl it was extracted with ethyl acetate, the combined organic phases were dried and evaporated. Purification of the residue by means of flash chromatography on silica gel (mobile solvent: ethyl acetate/heptane 1:2) yielded 14.4 g (68%) VI, melting point 109°-110° C. (ether).

Workup

  1. customto reach 0° C. for a short time
  2. temperatureThe internal temperature was gradually increased to -30° C.
  3. extractionwas extracted with ethyl acetate
  4. customthe combined organic phases were dried
  5. customevaporated
  6. customPurification of the residue by means of flash chromatography on silica gel (mobile solvent: ethyl acetate/heptane 1:2)

Sources & evidence

ORD record
ord-e1aa3216ef4c4a1fb552fae720596c8e
Source dataset
uspto-grants-1998_03
Patent number
US05731344

Linked notes

Loading…