70801-58-0Relevant academic research and scientific papers
I2/K2S2O8-Promoted ring-opening cyclizations of benzothiazoles and 3-oxo-3-arylpropanenitriles
Du, Mingxi,Gu, Yanlong,He, Jing,Li, Xuezhen,Liu, Ping,Vaccaro, Luigi,Zhang, Jie
, (2021/12/20)
An efficient I2/K2S2O8-promoted ring expansion of benzo[d]thiazole and 3-oxo-3-arylpropanenitrile has been developed. A variety of benzo[d]thiazole derivatives underwent the ring-opening cyclization smoothly to afford the diverse 3-aryl-4H-benzo[b][1,4]thiazine-2-carbonitriles in moderate to excellent yields. This protocol features metal-free reaction conditions, stable and available starting materials, and good group tolerance. The synthetic utility of this protocol was also demonstrated through gram-scale reaction and product derivatization. Mechanism studies indicate that the reaction may undergo a free radical process.
Umpolung Strategy with 2-Aminothiophenols: Access to 2-Arylbenzothiazine Derivatives from Alkyl Aryl Ketones
Nguyen, Thanh Binh,Retailleau, Pascal
supporting information, p. 5380 - 5384 (2020/11/02)
Strong Br?nsted acids were found to catalyze the oxidative condensation of 2-aminothiophenols with aryl alkyl ketones in DMSO to provide a wide range of complex 2-arylbenzothiazines. With acetophenones, dimeric 2-arylbenzothiazines were formed. On the other hand, the reaction with propiophenones resulted in 2:1 adducts whereas 1:1 adducts were produced with isobutyrophenones, benzoylacetonitrile and ethyl benzoylacetate. (Figure presented.).
Reaction between 2,2'-Dithiodianiline and Activated Alkynes. Synthesis of 4H-1,4-Benzothiazines
Liso, Gaetano,Trapani, Giuseppe,Reho, Antonia,Latrofa, Andrea,Loiodice, Fulvio
, p. 567 - 572 (2007/10/02)
By the title reaction acetylenic esters (2a-c), ketones (2d-g), and the nitrile (2h) gave in all cases the corresponding 4H-1,4-benzothiazines (3) together with other products whose nature depends on the alkyne used.Thus benzothiazoline and/or benzothiazole, benzothiazepine, and vinylsulphides were obtained in the representative cases (2c, f, h) studied in detail.Some of these latter compounds have been independently synthesised by reaction of 2-aminobenzenethiol with corresponding alkyne (2).In particular conditions by the reactions between 2,2'-dithiodianiline (1) and alkynes (2f, d) we isolated bisenamine compounds (19) and (20) respectively and their intermediacy in formation of the corresponding benzothiazines (3f) and (3d) was achieved.The mechanisms of the observed reactions are also suggested.
Oxidative Ring-Expansion of Benzothiazolines into 1,4-Benzothiazines
Liso, Gaetano,Trapani, Giuseppe,Latrofa, Andrea,Marchini, Paolo
, p. 279 - 282 (2007/10/02)
By treatment in boiling DMSO, benzothiazolines 1 yield 1,4-benzothiazines 4 in some cases together with benzothiazoles.Two competiting pathways, namely oxidative ring-expansion and decomposition of benzothiazoline accounting for the formation of 4 and benzothiazoles, respectively, are suggested.
