Downstream synthetic route of 185815-59-2

185815-59-2 4-Isobutyldihydro-2H-pyran-2,6(3H)-dione 11480690, aTetrahydropyrans compound, is more and more widely used in various fields.

185815-59-2, 4-Isobutyldihydro-2H-pyran-2,6(3H)-dione is a Tetrahydropyrans compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated

Example 4(5)-3-(2-(Cinnamyloxy)-2-oxoethyl)-5-methylhexanoic acid (III) – (opposite enantiomer to Example 3)Quinidine (17.2g, 52.8mmol) was suspended in toluene (23OmL). Cinnamyl alcohol (9.3 g, 69mmol) was added and the reaction mixture was cooled to -35 0C. The solution of 3- isobutylglutaric anhydride (9.Og, 52.8mmol) in toluene (6mL) was added during 15 min and the reaction mixture was stirred at -38 C for 24 hours. Working up is carried out analogously to the preparation of the compound from Example 3. Combined extracts were warmed to 35 0C and (S)- alpha-phenylethylamine (5.8 g, 48mmol) was added, followed by seed crystals (10 mg). The mixture was stirred for 4 hours at 25C and filtered to obtain 14.6 g of (5)-alpha-phenylethylamine salt of (S)- 3-(2-(cinnamyloxy)-2-oxoethyl)-5-methylhexanoic acid. Salt was suspended in toluene (90 mL) and stirred with 3% HCl (600 mL) until clear solution was obtained. Aqueous acidic solution was separated and organic layer was washed once again with 3% HCl (2OmL). Evaporation of toluene afforded 10.2 g (65%) of monoester as viscous yellowish oil. HPLC analysis on Chiralpak AS column, hexane/EtOH/TFA=95/5/0.1 revealed 91.4 % ee.1H NMR (CDCl3), delta/ppm: 0.87 (d, 6H, J=6.5 Hz), 1.21-1.27 (m, 2H), 1.56-1.70 (m, IH), 2.38-2.48 (m, 5H), 4.73 (dd, 2H, Jy=6.5 Hz, J2=1.2 Hz), 6.27 (dt, IH J/=15.8 Hz, J2=6.5 Hz), 6.65 (d, IH, J=15.8 HZ), 7.22-7.40 (m, 2H).13C NMR (CDCl3), delta/ppm: 22.34, 25.07, 29.64, 38.30, 38.48, 43.26, 64.92, 122.95, 126.50, 127.96, 128.49, 134.18, 136.07, 172.26, 178.64., 185815-59-2

185815-59-2 4-Isobutyldihydro-2H-pyran-2,6(3H)-dione 11480690, aTetrahydropyrans compound, is more and more widely used in various fields.

Reference£º
Patent; PLIVA ISTRAZIVANJE I RAZVOJ D.O.O.; MCLEISH, Nicholas, Alistair, Maxwell; WO2008/9897; (2008); A1;,
Tetrahydropyran – Wikipedia
Tetrahydropyran – an overview | ScienceDirect Topics