Chemoenzymatic synthesis of both enantiomers of 3-hydroxy-2,3-dihydro-4H-chromen-4-one

Demir, AS
Aybey, A
Sesenoglu, O
Polat, Faruk
4-Oxo-3,4-dihydro-2-chromen-3-yl acetate is synthesized using manganese(III)acetate starting from 2,3-dihydro-4H-chromen-4-one. K2CO3 mediated hydrolysis of 4-oxo-3,4-dihdro-2-chromen-3-yl acetate furnished 3-hydroxy-2,3-dihydro-4H-chromen-4-one in high yield. The enantioselective hydrolysis of (+/-)-4-oxo-3,4-dihydro-2-chromen-3-yI acetate in various organic solvent-phosphate buffer (pH7) systems and enantioselective transesterification of (+/-)-3-hydroxy-2,3-dihydro-4H-chromen-4-one in organic solvents was investigated by screening a range of lipases. The lipase Amano PS, PPL, PLE and CCL-catalyzed asymmetric ester hydrolysis and transesterification afforded the enantiomers of 3-hydroxy-2,3-dihydro-4H-chromen-4-one and 4-oxo-3,4-dihydro-2-chromen-3-yI acetate with high enantiomeric excess (up to 97% ee) and in good yields.


Chemoenzymatic synthesis of both enantiomers of 2-chloro-1-(2-furyl)ethanol
Gercek, Z; Karakaya, D; Demir, Ayhan Sıtkı (Elsevier BV, 2005-05-23)
Enzyme catalyzed transesterification of rac-2-chloro-1-(2-furyl)ethanol rac-1 using vinyl acetate afforded the enantiomers of 2-chloro-1-(2-furyl)ethanol 1 and 2-chloro-1-(2-furyl)ethyl acetate 2 in high enantiomeric excess. Several lipases were used for the kinetic resolution of racemic 2-chloro-1-(2-furyl)ethanol l, in which the lipases from Pseudomonas cepacia, Candida antarctica and Candida cylindracea displayed high enantioselectivity towards 1.
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Tanyeli, Cihangir; Akhmedov, M (Elsevier BV, 2004-06-07)
alpha,beta-Unsaturated and saturated cyclic ketones were selectively oxidized at the alpha'- and alpha-positions using Mn(OAc)(3) and Pb(OAc)(4), respectively, resulting in high chemical yields. The resultant racemic alpha'- and alpha-acetoxylated substrates were resolved into corresponding enantiomerically enriched alpha'- and alpha-hydroxylated and acetoxylated compounds with 96-98% ee via PLE hydrolysis. The absolute configurations of alpha'-acetoxy-alpha,beta-unsaturated cyclic ketones were determined b...
Chemoenzymatic synthesis of enantiomerically enriched 2-oxobicyclo[m.1.0]alkan-3-yl acetate derivatives
ÖZDEMİRHAN, FAZİLET DEVRİM; ÇELİK, MURAT; ATLI, SELİN; Tanyeli, Cihangir (Elsevier BV, 2006-01-23)
Racemic alpha'-acetoxy alpha,beta-unsaturated cyclopentanone and cyclohexanone have been resolved into the corresponding enantiomerically enriched alpha'-hydroxylated and acetoxylated compounds with 96-97% ee via PLE hydrolysis. Stereoselectivity in the palladium(II)-catalyzed reaction between the enantiomerically enriched alpha'-acetoxylated compounds and diazomethane has been investigated. In the alpha'-acetoxylated cyclopentenone, preferential cyclopropanation occurs in the anti-form, whereas alpha'-acet...
Amination/annulation of chlorobutenones with chiral amine compounds: synthesis of 1,2,4-trisubstituted pyrroles
Demir, Ayhan Sıtkı; Igdir, AC; Gunay, NB (Elsevier BV, 2005-10-03)
A series of 1,2,4-trisubstituted pyrroles have been synthesized in 83-96% yields on treatment of chiral primary amines, amino alcohols and esters of alpha-amino acids with different chlorobutenones in benzene-triethylamine. The conversions proceed without racemization.
Organosilanols as Catalysts in Asymmetric Aryl Transfer Reactions
Özçubukçu, Salih; BOLM, Carsten (American Chemical Society (ACS), 2005-03-01)
Various ferrocene-based organosilanols have been synthesized in four steps starting from achiral ferrocene carboxylic acid. Applying these novel planar-chiral ferrocenes as catalysts in asymmetric phenyl transfer reactions to substituted benzaldehydes afforded products with high enantiomeric excesses. The best result (91% ee) was achieved in the addition to p-chlorobenzaldehyde with organosilanol 2b, which has a tert-butyl substituent on the oxazoline ring and an isopropyl group on the silanol fragment.
Citation Formats
A. Demir, A. Aybey, O. Sesenoglu, and F. Polat, “Chemoenzymatic synthesis of both enantiomers of 3-hydroxy-2,3-dihydro-4H-chromen-4-one,” TETRAHEDRON-ASYMMETRY, pp. 1489–1493, 2003, Accessed: 00, 2020. [Online]. Available: