Triphenylphosphine → HCID 10707397, compound

Participants

Reaction Conditions

Reaction Steps

Diethyl azodicarboxylate (2.2 mL) was added to a cold (−15° C.) stirred solution of triphenyl phosphine (3.67 g) in tetrahydrofuran (40 mL). After stirring at 0° C. for 100 min, a solution of N-tert-butoxycarbonyl-trans-4-hydroxy-L-proline methyl ester (2.29 g) in tetrahydrofuran (20 mL) and formic acid (2.20 mL) were added. The mixture was stirred at room temperature for 14 hr, the solvent was removed and coevaporated several times with toluene in vacuo. The residue was diluted with toluene and precipitated solids were removed by filtration which was washed with toluene. The combined organic layers were evaporated in vacuo and the residue was purified by silica gel column chromatography (chloroform then chloroform:methanol=15:1, v/v) to give the title compound (4.07 g) as a pale yellow oil: 1H NMR (400 MHz, CDCl3) δ 1.39-1.50 (m, 9H), 2.25-2.34 (m, 1H), 2.43-2.60 (m, 1H), 3.54-3.67 (m, 1H), 3.72-3.83 (m, 1H), 3.75 (s, 3H), 4.37-4.55 (m, 1H), 5.35-4.41 (m, 1H), and 7.97 (s, 1H).

Provenance & Evidence