Chemoenzymatic synthesis of alpha(1)- and alpha-acetoxylated cyclic ketones

Tanyeli, Cihangir
Akhmedov, M
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 by transforming them into the corresponding saturated alpha-acetoxy cyclic ketones of known absolute configuration.


Chemoenzymatic synthesis of enantiomerically enriched 2-oxobicyclo[m.1.0]alkan-3-yl acetate derivatives
Atlı, Selin; Tanyeli, Cihangir; Department of Chemistry (2005)
a,β-Unsaturated cyclic ketones were selectively oxidized on a'- positions using Mn(OAc)3 and Pb(OAc)4, respectively. The resultant racemic a'-acetoxylated substrates were resolved into corresponding enantiomerically enriched a'-hydroxylated and a'-acetoxylated compounds via PLE hydrolysis. a'-Hydroxylated compounds are racemized quickly, so they were acetylated with acetyl chloride and pyridine in situ to give the corresponding a'-acetoxylated compounds. Resultant a'-acetoxy a,β-unsaturated cyclic ketones r...
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.
Catalytic enantioselective addition of diethylzinc to aldehydes using aziridine based chiral ligands
BULUT, Adnan; ASLAN, Ayhan; İZGÜ, Enver Cagri; Doğan, Özdemir (Elsevier BV, 2007-05-16)
The readily available ferrocenyl substituted aziridinylmethanol 1 (FAM-1) was used as a chiral catalyst in the diethylzinc addition reaction to aromatic and aliphatic aldehydes to give secondary alcohols in high yields and up to 99% enantiomeric excess at room temperature. The catalyst can be recovered and used without losing its activity.
A bis-Lewis basic 2-aminoDMAP/prolinamide organocatalyst for application to the enantioselective synthesis of Warfarin and derivatives
IŞIK, Murat; Akkoca, H. Ufuk; Akhmedov, I. Mecidoglu; Tanyeli, Cihangir (Elsevier BV, 2016-06-01)
A new chiral sec-amine/amidine-base hybrid catalyst, 2-aminoDMAP/prolinamide, is reported, which is able to catalyze conjugate addition of 4-hydroxycoumarin and various benzylideneacetones, a reaction that directly gives anticoagulant Warfarin and its analogues, with good yields (70-87%) and enantioselectivities (58-72%).
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...
Citation Formats
C. Tanyeli and M. Akhmedov, “Chemoenzymatic synthesis of alpha(1)- and alpha-acetoxylated cyclic ketones,” TETRAHEDRON-ASYMMETRY, pp. 1729–1733, 2004, Accessed: 00, 2020. [Online]. Available: