230642-84-9Relevant articles and documents
A practical pilot-scale synthesis of 4-vinyl-2,3-dihydrobenzofuran using imidate ester chemistry and phase-transfer catalysis
Rao, Meena,Yang, Ming,Kuehner, Daniel,Grosso, John,Deshpande, Rajendra P.
, p. 547 - 550 (2003)
A two-step telescoped synthesis of 4-vinyl-2,3-dihydrobenzofuran (2) was demonstrated using imidate ester chemistry and phase-transfer catalysis. Treatment of 2,3-bis(2-hydroxyethyl)-phenol (1) with the Vilsmeier reagent resulted in an in situ generation of a bis-imidate intermediate 4, which was converted to 4-(2-chloroethyl)-2,3-dihydrobenzofuran (6) via a sequential ring closure and chloride displacement reactions. Further dehydrohalogenation of 6 using a phase-transfer catalyst provided an excellent, cost-effective method to prepare high quality 4-vinyl-2,3-dihydrobenzofuran (2). The yields for the two-step telescoped process ranged from 83 to 90%.
Gram-Scale Synthesis of Chiral Cyclopropane-Containing Drugs and Drug Precursors with Engineered Myoglobin Catalysts Featuring Complementary Stereoselectivity
Bajaj, Priyanka,Sreenilayam, Gopeekrishnan,Tyagi, Vikas,Fasan, Rudi
, p. 16110 - 16114 (2016/12/26)
Engineered hemoproteins have recently emerged as promising systems for promoting asymmetric cyclopropanations, but variants featuring predictable, complementary stereoselectivity in these reactions have remained elusive. In this study, a rationally driven strategy was implemented and applied to engineer myoglobin variants capable of providing access to 1-carboxy-2-aryl-cyclopropanes with high trans-(1R,2R) selectivity and catalytic activity. The stereoselectivity of these cyclopropanation biocatalysts complements that of trans-(1S,2S)-selective variants developed here and previously. In combination with whole-cell biotransformations, these stereocomplementary biocatalysts enabled the multigram synthesis of the chiral cyclopropane core of four drugs (Tranylcypromine, Tasimelteon, Ticagrelor, and a TRPV1 inhibitor) in high yield and with excellent diastereo- and enantioselectivity (98–99.9% de; 96–99.9% ee). These biocatalytic strategies outperform currently available methods to produce these drugs.
A facile and practical synthesis of (-)-tasimelteon
Mi, Senyang,Sun, Xinzhe,Wu, Chaogang,Zhang, Xingxian
, p. 667 - 669 (2016/11/18)
An efficient and practical route for the synthesis of (-)-tasimelteon from 2,3-bis(2-hydroxyethyl)phenol has been developed. The product was prepared in seven steps in overall 16.4% yield using highly stereoselective cyclopropanation reaction of the intermediate as the key step.
