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Articles 1 - 3 of 3
Full-Text Articles in Physical Sciences and Mathematics
Synthesis And Application Of L-Proline And R-Phenylglycine Derived Organocatalysts For Direct Asymmetric Michael Addition Of Cyclohexanone To Nitroalkenes, Hayri̇ye Nevi̇n Naziroğlu, Abdulkadi̇r Sirit
Synthesis And Application Of L-Proline And R-Phenylglycine Derived Organocatalysts For Direct Asymmetric Michael Addition Of Cyclohexanone To Nitroalkenes, Hayri̇ye Nevi̇n Naziroğlu, Abdulkadi̇r Sirit
Turkish Journal of Chemistry
Novel R-phenylglycine derived organocatalysts were prepared from the reaction of Cbz-R-phenylglycine with indoline, pyrrolidine, or (S)-(-)-2-(diphenylmethyl)pyrrolidine in 3 steps. The asymmetric Michael addition of cyclohexanone to nitroolefins was investigated using R-phenylglycine derivatives along with L-prolinamides as chiral catalysts. The desired products were obtained in excellent yields with enantioselectivities up to 90% ee and diastereomeric ratio up to 98:2 of the syn }addition product.
Solvent-Free Michael Addition Of 2-Cyclohexenone Under Ultrasonic Irradiation In The Presence Of Long Chain Dicationic Ammonium Salts, Aytek Öge, Murat Emrah Mavi̇ş, Çi̇ğdem Yolaçan, Feray Aydoğan
Solvent-Free Michael Addition Of 2-Cyclohexenone Under Ultrasonic Irradiation In The Presence Of Long Chain Dicationic Ammonium Salts, Aytek Öge, Murat Emrah Mavi̇ş, Çi̇ğdem Yolaçan, Feray Aydoğan
Turkish Journal of Chemistry
Long chain dicationic ammonium salts (1a-1c), easily prepared from tert-amines and dihaloalkanes, were successfully used as efficient phase-transfer catalysts in the Michael addition reaction of various active methylene compounds to 2-cyclohexenone without solvent under ultrasonic irradiation. The investigated dicationic salts were more effective than monocationic tetrabutylammonium bromide, with short reaction times and high yields. This methodology was established under phase-transfer catalytic conditions and ultrasonic effects with many advantages, including the easy and cost-effective synthesis of the catalyst, mild reaction conditions, short reaction times, good yields, simple work-up procedures, and environmental friendliness.
The Reaction Of Dialkyl Acetylenedicarboxylates With 2-Oxo-2-Phenylacetaldehyde In The Presence Of Primary Amines: Synthesis Of Alkyl 2-Benzoyl-4-Alkylamino-5-Oxo-2,5-Dihydro-3-Furan Carboxylate Derivatives, Javad Safaei Ghomi, Fariba Salimi, Ali Ramazani, Fatemeh Zeinali Nasrabadi, Yavar Ahmadi
The Reaction Of Dialkyl Acetylenedicarboxylates With 2-Oxo-2-Phenylacetaldehyde In The Presence Of Primary Amines: Synthesis Of Alkyl 2-Benzoyl-4-Alkylamino-5-Oxo-2,5-Dihydro-3-Furan Carboxylate Derivatives, Javad Safaei Ghomi, Fariba Salimi, Ali Ramazani, Fatemeh Zeinali Nasrabadi, Yavar Ahmadi
Turkish Journal of Chemistry
A 3-component domino reaction approach between a primary amine, a dialkyl acetylenedicarboxylate, and 2-oxo-2- phenylacetaldehyde that affords novel alkyl 2-benzoyl-4-alkylamino- 5-oxo-2,5-dihydro-3-furan carboxylate derivatives is reported. The reaction sequence consists of an initial Michael addition of primary amines to dialkyl acetylenedicarboxylates, followed by an aldol-like reaction with 2-oxo-2-phenylacetaldehyde, and then \gamma -lactonization to afford the products. This cascade reaction sequence represents a rapid and unprecedented route to the described biologically interesting molecules.