Synthesis of various camphor-based chiral pyridine derivatives

Işık, Murat
Chiral aromatic nitrogen heterocycles are finding many applications in asymmetric organic synthesis, particularly as ligands in the preparation of chiral metal complexes. Since camphor-based chiral auxiliaries are known to be especially effective, a number of pyridines fused to the camphor skeleton have been reported. It is well known that nicotinic acid and its derivatives exhibiting qualitatively the biological activity of nicotinamide, which acts as an electron acceptor in many biological redox reactions. In connection to our works, we attempted to develop short and convenient way to prepare various camphorderived chiral pyridine or nicotinic acid derivatives. Here we report our results obtained from the annulation of (+)- b- hydroxymethylenecamphor as the feasible chiral pool with various enamines derived from active methylene compounds. (+)- b- Hydroxymethylenecamphor prepared from cheap and easily available natural (+)-camphor and enamines were transformed into chiral camphor-based pyridine derivatives via tandem condensation reaction in good yields.


Synthesis of heterocyclic amine substituted novel 1,4-Aminoalcohols and applications in various asymmetric transformations
Keskin, Eda; Tanyeli, Cihangir; Department of Chemistry (2007)
Aminoalcohols are very important compounds used in various asymmetric transformations as chiral ligands or chiral auxiliaries. In this thesis, four novel heterocyclic amine substituted chiral 1,4-aminoalcohols were synthesized. In the synthetic strategy, amide esters were synthesized from (2S, 3R)-3-methoxycarbonylbicyclo[2.2.1]hept-5-ene-2-carboxylic acid by DCC coupling method. Subsequent reduction of these amide esters lead to target 1,4-aminoalcohols. The activities of these novel chiral 1,4-aminoalcoho...
Synthesis of chiral lactones via the baeyer villiger oxidation of cyclic aromatic acetoxy ketones novel annulation reactions of 2-propynyl-1,3-dicarbonyl compounds to form pyrroles addition of acyl phosphonates to diethyl cyanophosphonate (depc)
Aybey, Asuman; Demir, Ayhan Sıtkı; Department of Chemistry (2009)
Chiral Baeyer-Villiger (BV) oxidation of cyclic ketones allows rapid access to asymmetric lactones as valuable intermediates in organic chemistry and frequently encountered precursors in enantioselective synthesis. In the first part, BV oxidation of functionalized ketones, especially cyclic -hydroxy and acetoxy ketones is described which could be a straightforward route to the -hydroxy lactones and -hydroxyalkanoic acid derivatives. The -acetoxylation of indanone, tetralone and chromanone derivatives by usi...
Generation of acyl anion equivalents from acylphosphonates via phosphonate-phosphate rearrangement: A highly practical method for cross-benzoin reaction
Demir, Ayhan Sıtkı; Reis, O; Igdir, AC; Esiringu, I; Eymur, S (American Chemical Society (ACS), 2005-12-09)
Acylphosphonates are potent acyl anion precursors that generate acyl anion equivalents under the promotion of cyanide anion via phosphonate-phosphate rearrangement. These anions readily react with aldehydes to provide cross-benzoin products. In this way it is possible to synthesize a variety of aromatic-aromatic, aromatic-aliphatic, and aliphatic-aromatic benzoins. Moreover the reaction of benzoylphosphonate with potent electrophile 2,2,2-trifluoroacetophenone provided the corresponding aldehyde-ketone coup...
Reactions of 2-substituted epichlorohydrins
Tanyeli, Cihangir; Akhmedov, IM; Ozgul, E; Kandemir, CG (Informa UK Limited, 1996-01-01)
2-Substituted epichlorohydrins have been synthesized by starting with 1,2-dichloro acetone and various alkyl and aryl halides via dichlorohydrins followed by cyclization. The reactive 2-substituted epichlorohydrins were subjected to nucleophilic attacking of azide and cyanide ions to afford corresponding beta-azido alcohols and alpha,beta-unsaturated nitriles.
Synthesis and enzymatic resolution of various cyclopentenoid and cyclohexenoid type compounds
İyigün, Çiğdem; Tanyeli, Cihangir; Department of Chemistry (2005)
The aim of this thesis is to synthesize enantiomerically enriched cyclopentenoid and cyclohexenoid type of compounds with quaternary carbon stereocenters that are the simplest precursors of the complex natural products. The first part of the study involves the preparation of ?'-acetoxy ?'-substituted ?,β-unsaturated cyclic ketones. Methylation, ethylation, benzylation and allylation of cyclohexenone and cyclopentenone derivatives are performed. Then, these compounds are regioselectively oxidized at the ?'-p...
Citation Formats
M. Işık, “Synthesis of various camphor-based chiral pyridine derivatives,” M.S. - Master of Science, Middle East Technical University, 2005.