160695-26-1Relevant articles and documents
Diastereoselective Electrochemical Carboxylation of Chiral α-Bromocarboxylic Acid Derivatives: An Easy Access to Unsymmetrical Alkylmalonic Ester Derivatives
Feroci, Marta,Orsini, Monica,Palombi, Laura,Sotgiu, Giovanni,Colapietro, Marcello,Inesi, Achille
, p. 487 - 494 (2004)
The diastereoselective electrochemical carboxylation of chiral N-(2-bromoacyl)oxazolidin-2-ones has been studied. This reaction was carried out by cathodic reduction of the C - Br bond, in the presence of carbon dioxide, followed by treatment with diazomethane. The yields and the diastereomeric ratio of the two epimeric alkylmalonic acid derivatives are strongly affected by various factors: solvent-supporting electrolyte system, temperature, electrode material, electrolysis conditions, oxazolidinone moiety. The higher yields (88%) were obtained starting from N-(2-bromopropionyl)-4R-phenyloxazolidin-2-one la, but with poor diastereoselectivity (61:39). The two epimers were easily separated by flash chromatography. The best results were achieved using a different chiral auxiliary: Oppolzer's camphor sultam. Starting from 1j a good yield in carboxylated product was obtained (80%) with excellent diastereoselectivity (98:2). These chiral alkylmalonic acid derivatives are valuable building blocks in the synthesis of molecules with biological activity and of chiral propane-1,3-diols derivatives.
Diastereoselective Electrophilic Trifluoromethylthiolation of Chiral Oxazolidinones: Access to Enantiopure α-SCF3 Alcohols
Chachignon, Hélène,Kondrashov, Evgeniy V.,Cahard, Dominique
, p. 965 - 971 (2018/01/27)
Lithium imide enolates featuring Evans’ chiral oxazolidinone auxiliary were involved in diastereoselective α-trifluoromethylthiolation with electrophilic SCF3 donors. Diastereopure products were isolated and converted to enantiopure α-SCF3 alcohols without racemisation. (Figure presented.).
PROCESS FOR THE PREPARATION OF (1S,3S,7S,10R,11S,12S,16R)-7,11-DIHYDROXY-8,8,10,12,16-PENTAMETHYL-3-[(1E)-1-METHYL-2-(2-METHYL-4-THIAZOLYL)ETHENYL]-17-OXA-4-AZABICYCLO[14.1.0]HEPTADECANE-5,9-DIONE AND INTERMEDIATES THEREOF
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Page/Page column 48-49, (2015/06/25)
The present invention relates to an improved process for the preparation of (1S,3S,7S,10R,11S,12S,16R)-7,11-dihydroxy-8,8,10,12,16-pentamethyl-3-[(1E)-1-methyl-2-(2- methyl-4-thiazolyl)ethenyl]- 17-oxa-4-azabicyclo[ 14.1.0]heptadecane-5,9-dione represented by the following structural formula I and intermediates thereof. The present invention also provides novel intermediate compounds useful for the preparation of compound of formula I and its intermediates.