The enantioselective synthesis of the potent dopamine D1 agonist (1R,3S)-3-(1'-adamantyl)-1-(aminomethyl)-3,4-dihydro-5,6-dihydroxy-1H-2-benzopyran (A77636)
摘要:
The synthesis of both enantiomers of the title compound is described. The corresponding racemic compound (+/-)-1 was previously shown to be a highly potent and selective dopamine Dl agonist. Key to the synthesis of the enantiomers was the oxazaborolidine-catalyzed asymmetric reduction of the alpha-bromomethyl ketone 12 which led to the optically enriched epoxide 7. An aryllithium addition to the epoxide followed by a diastereospecific cyclization to the isochroman system furnished compound 17, which was deprotected to afford (-)-1 with >99.5% optical purity.
Synthesis of enantiopure 1,2-azido and 1,2-amino alcohols via regio- and stereoselective ring-opening of enantiopure epoxides by sodium azide in hot water
作者:Hai-Yang Wang、Kun Huang、Melvin De Jesús、Sandraliz Espinosa、Luis E. Piñero-Santiago、Charles L. Barnes、Margarita Ortiz-Marciales
DOI:10.1016/j.tetasy.2015.12.002
日期:2016.2
A practical and convenient method for the efficient and regio- and stereoselective ring-opening of enantiopure monosubstituted epoxides by sodium azide under hydrolytic conditions is reported. The ring-opening of enantiopure styryl and pyridyl (S)-epoxides by N3 - in hot water takes place preferentially at the internal position with complete inversion of configuration to produce (R)-2-azido ethanols
Chiral Epoxides via Borane Reduction of 2-Haloketones Catalyzed by Spiroborate Ester: Application to the Synthesis of Optically Pure 1,2-Hydroxy Ethers and 1,2-Azido Alcohols
作者:Kun Huang、Haiyang Wang、Viatcheslav Stepanenko、Melvin De Jesús、Carilyn Torruellas、Wildeliz Correa、Margarita Ortiz-Marciales
DOI:10.1021/jo102294j
日期:2011.3.18
with 10% spiroaminoborate ester 1 as catalyst is described. By a simple basic workup of 2-halohydrins, optically active epoxides are obtained in high yield and with excellent enantiopurity (up to 99% ee). Ring-opening of oxiranes with phenoxides or sodium azide is investigated under different reaction conditions affording nonracemic 1,2-hydroxy ethers and 1,2-azido alcohols with excellent enantioselectivity
The enantioselective synthesis of the potent dopamine D1 agonist (1R,3S)-3-(1'-adamantyl)-1-(aminomethyl)-3,4-dihydro-5,6-dihydroxy-1H-2-benzopyran (A77636)
作者:Michael P. DeNinno、Richard J. Perner、Howard E. Morton、Stanley DiDomenico
DOI:10.1021/jo00052a025
日期:1992.12
The synthesis of both enantiomers of the title compound is described. The corresponding racemic compound (+/-)-1 was previously shown to be a highly potent and selective dopamine Dl agonist. Key to the synthesis of the enantiomers was the oxazaborolidine-catalyzed asymmetric reduction of the alpha-bromomethyl ketone 12 which led to the optically enriched epoxide 7. An aryllithium addition to the epoxide followed by a diastereospecific cyclization to the isochroman system furnished compound 17, which was deprotected to afford (-)-1 with >99.5% optical purity.