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ChemicalBook CAS DataBase List S- (+)-Rolipram
85416-73-5

S- (+)-Rolipram synthesis

11synthesis methods
-

Yield: 78%

Reaction Conditions:

Stage #1:ethyl (S)-3-[3-(cyclopentyloxy)-4-methoxyphenyl]-4-phthalimidobutanoate with hydrazine hydrate in tetrahydrofuran for 24 h;Inert atmosphere;
Stage #2: with triethylamine in toluene at 110; for 20 h;Inert atmosphere;

Steps:

Synthesis of (S)-Rolipram. 6
To a solution of 3an(0.2 mmol) in THF (10 mL) was added hydrazine hydrate (0.5 mL) and the solution was stirred for 24 h. After complete consumption of the starting material, the reaction mixture was extracted with dichloromethane and concentrated in vacuum, the residue was dissolved in a mixture of Et3N (0.6 mL) and toluene (3 mL) and the resultant solution heated at 110 °C for 20 h. After cooling to rt, the solvents were evaporated under reduced pressure. The residue was purified by flash chromatography (silica gel, ethyl acetate) to yield colorless crystals (78%).

References:

Han, Fuzhong;Chen, Jun;Zhang, Xiangyang;Liu, Jibing;Cun, Linfeng;Zhu, Jin;Deng, Jingen;Liao, Jian [Tetrahedron Letters,2011,vol. 52,# 7,p. 830 - 833] Location in patent:supporting information; experimental part

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