89321-71-1Relevant articles and documents
Efficient polymer-supported Sharpless alkene epoxidation catalyst
Canali, Laetitia,Karjalainen, Jaana K.,Sherrington, David C.,Hormi, Osmo
, p. 123 - 124 (1997)
Linear poly(tartrate ester) ligands provide high chemical yields and enantiomeric excesses in the epoxidation of trans-hex-2-en-1-ol using Ti(OPri)4-tert-butyl hydroperoxide.
Br?nsted acid promoted intramolecular cyclization of O-alkynyl benzoic acids: Concise total synthesis of exserolide F
Dumpala, Mohan,Kadari, Lingaswamy,Krishna, Palakodety Radha
, p. 2403 - 2408 (2018/08/29)
Herein we report the stereoselective total synthesis of Exserolide F. The key step involves triflic acid catalyzed highly regioselective intramolecular cyclization of an O-alkynyl benzoic acid derivative to accomplish the core isocoumarin skeleton of the natural product via 6-endo-dig mode of cyclization. The other important steps are: Sharpless asymmetric epoxidation, Barbier propargylation, Sonogashira coupling en route to access the O-alkynyl benzoic acid derivative.
Kinetic resolution of epoxy alcohols with the Sharpless Ti-isopropoxide/tartaric ester complex
Maljutenko, Karolin,Paju, Anne,J?rving, Ivar,Pehk, T?nis,Lopp, Margus
, p. 608 - 613 (2016/07/11)
When investigating the Sharpless epoxidation of enol-protected 4-hydroxy-1,2-cyclopentanediones, the ability of the asymmetric Ti(OiPr)4/tartaric ester complex to discriminate between enantiomeric epoxides formed in situ was discovered, leading to the epoxide opening reaction of only one enantiomer. This observation was used in the kinetic resolution of racemic substituted 2,3-epoxy-4-hydroxy-cyclopentanol, to afford enantiomerically enriched epoxyalcohols in good yields and with ees up to 96%.
Asymmetric epoxidation of allylic alcohols catalyzed by vanadium-binaphthylbishydroxamic acid complex
Noji, Masahiro,Kobayashi, Toshihiro,Uechi, Yuria,Kikuchi, Asami,Kondo, Hisako,Sugiyama, Shigeo,Ishii, Keitaro
supporting information, p. 3203 - 3210 (2015/03/30)
A vanadium-binaphthylbishydroxamic acid (BBHA) complex-catalyzed asymmetric epoxidation of allylic alcohols is described. The optically active binaphthyl-based ligands BBHA 2a and 2b were synthesized from (S)-1,1'-binaphthyl-2,2'dicarboxylic acid and N-substituted-O-trimethylsilyl (TMS)-protected hydroxylamines via a one-pot, three-step procedure. The epoxidations of 2,3,3-trisubstituted allylic alcohols using the vanadium complex of 2a were easily performed in toluene with a TBHP water solution to afford (2R)-epoxy alcohols in good to excellent enantioselectivities.