Synthesis of spiro-containing 1,4-oxazepines from N-propargylic beta-enaminones

Karadeniz, Eda
Kelgökmen, Yılmaz
Zora, Metin
An efficient and general method for the synthesis of spiro‐1,4‐oxazepines and 3,3‐dimethyl‐1,4‐oxazepines is reported. When treated with ZnI2 and AgSbF6 in refluxing DCE, cyclohexane‐embedded N‐propargylic β‐enaminones underwent 7‐exo‐dig cyclization to afford spiro‐1,4‐oxazepines, specifically 12‐methylene‐11‐oxa‐7‐azaspiro[5.6]dodeca‐7,9‐dienes, in good to high yields. Accordingly, N‐(1,1‐dimethyl)propargylic β‐enaminones produced 3,3‐dimethyl‐1,4‐oxazepines. Cyclization was found to be general for a diverse range of N‐propargylic β‐enaminones with high efficiency and broad functional group tolerance. This operationally easy method might provide quick access to a library of functionalized spiro and gem‐dimethyl‐substituted 1,4‐oxazepine derivatives of pharmacological interest.


Synthesis of 3-[(4-Nitrophenyl)thio]-Substituted 4-Methylene-1-pyrrolines from N-Propargylic beta-Enaminones
Korkmaz, Esra; Zora, Metin (American Chemical Society (ACS), 2020-04-03)
A facile and efficient method for the synthesis of 3-[(4-nitrophenyl)thio]-substituted 4-methylene-1-pyrrolines is described. When treated with 4-nitrobenzenesulfenyl chloride in refluxing acetonitrile, N-propargylic beta-enaminones produced alpha-sulfenylated N-propargylic beta-enaminones, which, in the presence of sodium hydride or cesium carbonate, underwent nucleophilic cyclization to afford 4-methylene-3-[(4-nitrophenyl)thio]-1-pyrrolines in good to high yields. It was shown for the first time that on ...
A new approach for the synthesis of spiro and gem-dimethyl-substituted 1,4-oxazepines from N-propargylic beta-enaminones
Karadeniz, Eda; Kelgökmen, Yılmaz; Zora, Metin (Wiley, 2020-11-01)
An efficient and general method for the synthesis of spiro-1,4-oxazepines and 3,3-dimethyl-1,4-oxazepines is reported. When treated with ZnI2 and AgSbF6 in refluxing DCE, cyclohexane-embedded N-propargylic beta-enaminones underwent 7-exo-dig cyclization to afford spiro-1,4-oxazepines, specifically 12-methylene-11-oxa-7-azaspiro[5.6]dodeca-7,9-dienes, in good to high yields. Accordingly, N-(1,1-dimethyl)propargylic beta-enaminones produced 3,3-dimethyl-1,4-oxazepines. Cyclization was found to be general for ...
Synthesis of ferrocenyl quinolines
Zora, Metin (Elsevier BV, 2008-06-01)
A convenient one-pot synthesis of ferrocenyl-substituted quinolines via a molecular iodine-catalyzed reaction of ferrocenylimines with enolizable aldehydes is reported. First, nucleophilic addition of the in situ generated enol to ferrocenylimine produces beta-anilinopropionaldehyde, which then undergoes intramolecular Friedel-Crafts reaction to give dihydroquinoline derivative. Finally, subsequent dehydration and aerobic oxidation affords ferrocenyl quinolines.
Synthesis of beta-chloro-alpha-aminophosphonate derivatives via the regioselective ring opening of unactivated aziridine-2-phosphonates
Polat-Cakir, Sidika; BEKSULTANOVA, Nurzhan; Doğan, Özdemir (Informa UK Limited, 2018-12-02)
A series of unactivated racemic and chiral aziridine-2-phosphonates were synthesized by modified Gabriel-Cromwell reaction. Ring opening reaction of the synthesized phosphonates by gaseous HCl provided access to a wide range of biologically interesting novel beta-chloro-alpha-aminophosphonates. All reactions toward each of the above-mentioned products can be conducted regioselectively in high yields.
Synthesis of 1,4-Thiazepines
Kelgokmen, Yılmaz; Zora, Metin (American Chemical Society (ACS), 2018-08-03)
An efficient, general, and unprecedented methodology for the synthesis of 2-methylene-2,3-dihydro-1,4-thiazepines from N-propargylic beta-enaminones is described. Initially, N-propargylic beta-enaminones were thionated with Lawesson's reagent in good to high yields, and then the resulting N-propargylic beta-enaminothiones were subjected to electrophilic cyclization. When treated with zinc chloride in refluxing chloroform, Npropargylic beta-enaminothiones underwent electrophilic cyclization to yield 2-methyl...
Citation Formats
E. Karadeniz, Y. Kelgökmen, and M. Zora, “Synthesis of spiro-containing 1,4-oxazepines from N-propargylic beta-enaminones,” 2018, vol. 255, Accessed: 00, 2020. [Online]. Available: