1203-15-2Relevant academic research and scientific papers
Enantioselective hydroesterificative cyclization of 1,6-enynes to chiral γ-lactams bearing a quaternary carbon stereocenter
Dong, Kaiwu,Li, Huimin,Ren, Xinyi,Shen, Chaoren,Tang, Lin,Wang, Peng
supporting information, p. 3561 - 3566 (2021/05/29)
A palladium-catalyzed asymmetric hydroesterification-cyclization of 1,6-enynes with CO and alcohol was developed to efficiently prepare a variety of enantioenriched γ-lactams bearing a chiral quaternary carbon center and a carboxylic ester group. The approach featured good to high chemo-, region-, and enantioselectivities, high atom economy, and mild reaction conditions as well as broad substrate scope. The correlation between the multiple selectivities of such process and the N-substitutes of the amide linker in the 1,6-enyne substrate has been depicted by the crystallographic evidence and control experiments.
UV Light Induced Direct Synthesis of Phenanthrene Derivatives from a Linear 3-Aryl-N-(arylsulfonyl) Propiolamides
Chen, Ming,Yang, Chao,Wang, Yanpei,Li, Dazhi,Xia, Wujiong
supporting information, p. 2280 - 2283 (2016/06/01)
A novel photochemical approach for the synthesis of phenanthrene derivatives from linear 3-aryl-N-(arylsulfonyl) propiolamides via a tandem radical Smiles rearrangement/C-S bonding/Mallory reaction is disclosed. The control experiment results and isolation of the key intermediates give further insight into the reaction mechanism. Gram scale reaction using a flow reactor demonstrated the synthetic potential applications of our protocol.
Diverse reactivity in a rhodium(III)-catalyzed oxidative coupling of N-allyl arenesulfonamides with alkynes
Wang, Dongqi,Wang, Fen,Song, Guoyong,Li, Xingwei
supporting information, p. 12348 - 12352 (2013/02/23)
Olefinic CiH activation of N-allyl sulfonamides in the presence of [{RhCpCl2}2] (Cp=Me5C5) enabled their oxidative coupling with alkynes to generate 1,2-dihydropyridines, pyridines, and cyclopentenones (see scheme; Ts=p-toluenesulfonyl). The type of highly substituted product formed was controlled by the substitution of the allyl group and the reaction conditions. Copyright
Aziridines, 61 +"--"+ Ring Opening of 2,2-Dimethyl-1-sulfonylaziridines by Anilines: Regioselectivity and Revised Structure of Main Products
Buchholz, Berthold,Lin, Pen-Yuan,Onistschenko, Andreas,Stamm, Helmut
, p. 483 - 487 (2007/10/02)
It is shown (1) that in the most reactions of anilines 2 with 1-sulfonyl-2,2-dimethylaziridines 1 both isomeric products 3 and 4 are formed, (2) that the "normal" product 4 obtained by attack on position 3 of 1 usually arises in a small or negligible amount that seems to decrease with decreasing basicity of 2, and (3) that the amount of 4 strongly increases with increasing steric demand of 2.Formation of 4 is explained by a lag of bond making in SN2. +"--"+ N-Aryl-N'-sulfonyl-gem-dimethylethylenediamines, 1-Sulfonyl-2,2-dimethylaziridines, Regioselectivity of Nucleophilic Ring Opening, Steric Hindrance Effect, Basicity Effect
Synthesis of the Pyrrolidine Ring System by Radical Cyclization
Padwa, Albert,Nimmesgern, Hildegard,Wong, George S. K.
, p. 5620 - 5627 (2007/10/02)
A series of bromo-substituted allyl- and diallyl-substituted sulfonamides have been found to undergo free radical cyclization when treated with tri-n-butyltin hydride in the presence of AIBN.The regiochemical course of the cyclization depends on the nature of the substituent groups attached to the ?-bond.The stereoelectronic factors governing the cyclization reaction of these N-allylsulfonamides are even more stringent than those which occur with the simple 5-hexenyl system.This is probably related to the shorter C-N bond distance which promotes the 5-exo trigcyclization pathway.The present method provides an attractive entry to the preparation of pyrrolidines from easily available N-(2-bromoethyl)-N-allyl- and N-(2-bromopropenyl)-N-allylsulfonamides.The method represents a clear-cut example of the use of hetero-substituted radicals in C-C bond-forming processes.
