Reference

Process for stereoselective epoxidation of a,b-unsaturated ketones

Buschmann, Helmut Heinrich; Torrens Jover, Antoni; Yenes Minguez, Susana; Pericas Brondo, Miguel Angel (Laboratorios del Dr. Esteve, S.A., Spain). PCT Int. Appl. WO 2007000329 A2 4 Jan 2007, 43pp. DESIGNATED STATES: W: AE, AG, AL, AM, AT, AU, AZ, BA, BB, BG, BR, BW, BY, BZ, CA, CH, CN, CO, CR, CU, CZ, DE, DK, DM, DZ, EC, EE, EG, ES, FI, GB, GD, GE, GH, GM, HN, HR, HU, ID, IL, IN, IS, JP, KE, KG, KM, KN, KP, KR, KZ, LA, LC, LK, LR, LS, LT, LU, LV, LY, MA, MD, MG, MK, MN, MW, MX, MZ, NA, NG, NI, NO, NZ, OM, PG, PH, PL, PT, RO, RS, RU, SC, SD, SE, SG, SK, SL, SM, SY, TJ, TM, TN, TR, TT, TZ, UA, UG, US, UZ, VC; RW: AT, BE, BF, BJ, CF, CG, CH, CI, CM, CY, DE, DK, ES, FI, FR, GA, GB, GR, IE, IS, IT, LU, MC, ML, MR, NE, NL, PT, SE, SN, TD, TG, TR.There are some reagents with their cas registry numbers 1191-47-5 and 62961-64-2 are used in this study. (English). (World Intellectual Property Organization). CODEN: PIXXD2. APPLICATION: WO 2006-EP6229 20 Jun 2006. PRIORITY: ES 2005-1567 27 Jun 2005. DOCUMENT TYPE: Patent CA Section: 27 (Heterocyclic Compounds (One Hetero Atom)) This invention provides a process for stereoselective epoxidn. of a,b-unsatd. ketones in the presence of a lanthanoid catalyst comprising a chiral diol or aminoalc. For example, trans-1,1,1-trifluoro-4-phenyl-3-buten-2-one was epoxidized with tert-Bu hydroperoxide in THF at 25 °C in the presence of (R)-BINOL, triphenylarsenic oxide, and tris(isopropoxy)samarium for 18 h to give trans-1,1,1-trifluoro-4-phenyl-3-buten-2-one epoxide with 53% e.e. (99% conversion). The obtained epoxides are useful intermediate for synthesizing chiral 5-phenyl-4,5-dihydropyrazole derivs. .