Benzenesulfonic acid, 4-methyl-, compd. with pyridine (1:1) → rel-(3AR,4R,5R,6aS)-4-((R,E)-3-hydroxy-5-phenylpent-1-en-1-yl)-2-oxohexahydro-2H-cyclopenta[b]furan-5-yl [1,1'-biphenyl]-4-carboxylate

Temperature

45 °C

Pyridinium p-toluenesulfonate (20 mg) was added to a stirred solution of the compound [8a] (0.44 g), obtained in previous step, in methanol (20 mL) at room temperature. The mixture was stirred at 40-50° C. for 3-4 hours (TLC monitoring) and evaporated under reduced pressure. The residue was diluted with dichloromethane (30 mL). The solution was washed with saturated aqueous solution of sodium bicarbonate (10 mL) and brine(10 mL), dried over sodium sulfate, filtered and evaporated to give 0.35 g (93.4%) of oily residue. The residue was crystallized from a mixture of hexane and ether to give compound [6a] as white crystals with mp 81-83° C. and [α]D20 −124.5° (c 1, MeCN). 1H NMR (CDCl3) δ: 7.08-8.05 (m, 14H); 5.51-5.74 (m, 2H); 5.21-5.30 (m, 1H); 5.02-5.07 (m, 1H); 4.09-4.13 (m, 1H); 2.46-2.92 (m, 7H); 2.18-2.28 (m, 1H); 1.66-1.86 (m, 3H). 13C (CDCl3) δ: 31.6; 34.8; 37.6; 38.7; 42.7; 54.1; 71.6; 79.0; 83.1; 125.9; 127.1; 127.2; 128.2; 128.3; 128.8; 128.9; 130.1; 136.2; 139.9; 141.5; 146.1; 165.9; 176.2.

1. customevaporated under reduced pressure
2. additionThe residue was diluted with dichloromethane (30 mL)
3. washThe solution was washed with saturated aqueous solution of sodium bicarbonate (10 mL) and brine(10 mL)
4. dry with materialdried over sodium sulfate
5. filtrationfiltered
6. customevaporated

ORD record

ord-0166745728584466aa72418ad4257ce1

Source dataset

uspto-grants-2005_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06927300B2