Reference

Preparation of (2R)-2-propyloctanoic acid

Preparation of (2R)-2-propyloctanoic acid. Hamada, Yasumasa; Hasegawa, Tomoyuki; Matsui, Toshiaki; Kasamatsu, Eiji (Ono Pharmaceutical Co., Ltd., Japan). PCT Int. Appl. WO 2004110972 A1 23 Dec 2004, 25 pp. 50418-68-3 which is the cas registry number is also used here. 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, HR, HU, ID, IL, IN, IS, JP, KE, KG, KP, KR, KZ, LC, LK, LR, LS, LT, LU, LV, MA, MD, MG, MK, MN, MW, MX, MZ, NA, NI, NO, NZ, OM, PG, PH, PL, PT, RO, RU, SC, SD, SE, SG, SK, SL, SY, TJ, TM, TN, TR, TT, TZ, UA, UG, US, UZ, VC, VN, YU, ZA, ZM, ZW; RW: AT, BE, BF, BJ, CF, CG, CH, CI, CM, CY, DE, DK, ES, FI, FR, GA, GB, GR, IE, IT, LU, MC, ML, MR, NE, NL, PT, SE, SN, TD, TG, TR. (Japanese). (World Intellectual Property Organization). CODEN: PIXXD2. CLASS: ICM: C07C051-06. ICS: C07C053-128; C07C231-06; C07C233-05; C07C309-73; C07M007-00. APPLICATION: WO 2004-JP8387 9 Jun 2004. PRIORITY: JP 2003-164485 10 Jun 2003. DOCUMENT TYPE: Patent CA Section: 23 (Aliphatic Compounds) A process for producing (2R)-2-propyloctanoic acid which comprises subjecting (2R)-2-hexyloxirane to a ring-opening reaction with carbon no. increase by 2, subsequently subjecting the reaction product to a hydroxy-protecting reaction to convert it into n-PrCH(X)(CH2)5Me (X = optionally protected hydroxy), subjecting the compd. to a reaction for increasing the no. of carbon atoms by 1 to convert it into (2R)-2-propyloctanamide, recrystg. the amide, and then hydrolyzing it. Thus, Grignard reaction of (2R)-2-hexyloxirane with EtMgCl gave, after treatment with TsCl, (1S)-1-propylheptyl p-toluenesulfonate, cyanation of which with NaCN followed by hydrolysis gave the title compd. .