Chemoenzymatic synthesis of enantiomerically enriched 2-oxobicyclo[m.1.0]alkan-3-yl acetate derivatives

Atlı, Selin
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 reacted with excess amount of diazomethane under the catalsts of Pd(OAc)2 to give the resulting bicyclic diastereomeric products. At the end of the experiment, Enantiomeically enriched 2-oxobicyclo[3.1.0]hexan-3-yl acetate and 2-oxobicyclo[4.1.0]heptan-3-yl acetate were chemoenzymatically synthesized.


Chemoenzymatic synthesis of chiral hydroxymethyl cycloalkenols
Şenocak, Deniz; Demir, Ayhan Sıtkı; Department of Chemistry (2004)
Chiral cyclic alkenols with hydroxymethyl functionality are important structural units in many biologically active natural compouds such as prostaglandins, sesquiterpene antiviral agents, pentenomycins, xanthocidin, sarkomycin, etc. 1,3-cycloalkanediones are converted into bicyclic polyoxo derivatives with formaldehyde and trioxane in the presence of Lewis acid. Selective oxidation of the bicyclic compounds by using manganese(III)acetate followed by enzyme-catalyzed kinetic resolution afforded chiral bicycl...
Chemoenzymatic synthesis of alpha(1)- and alpha-acetoxylated cyclic ketones
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...
A facile synthesis of various butenolides
Tanyeli, Cihangir (Informa UK Limited, 2000-01-01)
The synthesis of alpha'-acyloxy-alpha,beta-unsaturated cyclic ketones from the corresponding alpha,beta-unsaturated cyclic ketones by using manganese (III) acetate in combination with 2-chloropropionic acid followed by subsequent Arbuzov and intramolecular Horner-Emmons cyclization reactions provided a convenient synthetic pathway to various butenolides 4a-d.
Fam-zinc catalyzed asymmetric 1,3-dipolar cycloaddition reactions of azomethine ylides and
Koyuncu, Hasan; Doğan, Özdemir; Department of Chemistry (2007)
In the first part of this study, four new chiral ligands (FAM) were synthesized and used in catalytic amounts in asymmetric 1,3-dipolar cycloaddition reactions of azomethine ylides. This method leads to the synthesis of chiral pyrrolidines, which are found in the structure of many biologically active natural compounds and drugs. It was found that using 10 mol% of one of these chiral ligands with different dipolarophiles (dimethyl maleate, dimethyl fumarate, methyl acrylate, tert-butyl acrylate, and Nmethylm...
Demir, Ayhan Sıtkı; SAATCIOGLU, A (Informa UK Limited, 1993-01-01)
The alpha'-oxidation of cyclic derivatives of alpha-alkoxy-alpha,beta-unsaturated ketones using manganese(III)acetate in the presence of various carboxylic acids provided a convenient synthesis of 5-acyloxy-2-alkoxy-2-cyclopentenones and 6-acyloxy-2-alkoxy-2-cyclohexenones.
Citation Formats
S. Atlı, “Chemoenzymatic synthesis of enantiomerically enriched 2-oxobicyclo[m.1.0]alkan-3-yl acetate derivatives,” M.S. - Master of Science, Middle East Technical University, 2005.