92802-07-8Relevant articles and documents
[4+1] Cycloaddition of Enaminothiones and Aldehyde N-Tosylhydrazones Toward 3-Aminothiophenes
Liu, Zhuqing,Wu, Ping,He, Yuan,Yang, Ting,Yu, Zhengkun
supporting information, p. 4381 - 4392 (2018/10/15)
An efficient protocol toward trisubstituted 3-aminothiophenes has been developed through a [4+1] cycloaddition of enaminothiones and aldehyde N-tosylhydrazones under transition-metal-free conditions. 3-Aminothiophene derivatives as well as their chiral analogs were obtained in good to excellent yields. Direct interaction of the enaminothiones with the diazo compounds of α-carbonyl or ester group-functionalized aldehydes also efficiently afforded the same type of 3-aminothiophenes. The diversity of the synthetic methodology has been demonstrated by the broad substrate scopes and excellent chemoselectivity in cleavage of the C?S, C?O, and C?N bonds in enaminothiones. (Figure presented.).
Novel synthesis of 5,6-dihydro-4H-thieno[3,2-b]pyrrol-5-ones via the rhodium(II)-mediated Wolff rearrangement of 3-(thieno-2-yl)-3-oxo-2-diazopropanoates
Lee, Dong Joon,Kim, Kyongtae,Park, Yung Ja
, p. 873 - 876 (2007/10/03)
(equation presented) Treatment of thioaryolketene S,N-acetals 12 with Hg(OAc)2 followed by addition of 2-diazo-3-trimethylsilyloxy-3-butenoic acid alkyl esters 15 in CH2Cl2 at room temperature gave 3-(3-alkylamino-5-arylth
Rhodium(II)-mediated reactions of thiobenzoylketene S,N-acetals with α-diazo carbonyl compounds: Synthesis of 2-substituted 3-alkylamino-5-phenylthiophenes
Song, Hyun Min,Kim, Kyongtae
, p. 2414 - 2417 (2007/10/03)
Treatment of 3-methylamino-3-methylsulfanyl-1-phenylpropenethione 1 with excess (2.5 equiv.) α-diazo carbonyl compounds such as α-diazoketones and α-diazoesters in the presence of a catalytic amount of Rh(II) acetate in CH2Cl2 at rt gave 2-acyl- or 2-aroyl-3-methylamino-5-phenylthiophenes and alkyl 3-methylamino-5-phenylthiophene-2-carboxylates, respectively, as major products along with 1-phenyl-2-methylsulfanylethanones. The formation of the major products indicates that the carbenes or carbenoids generated interact initially with the thione sulfur of 1.
A facile and convenient synthesis of 3-alkylamino-5-arylthiophenes with a variety of substituents at C-2 and studies of reaction mechanisms
Kim, Bo Sung,Kim, Kyongtae
, p. 3690 - 3699 (2007/10/03)
Thioaroylketene S,N-acetals were treated with active methylene compounds including β-keto ester, nitromethane, cyanoacetic acid, p- toluenesulfonylacetone, 4-nitrophenylacetic acid, and diethyl (2- oxopropyl)phosphonate in the presence of mercury(II) acetate in CH2Cl2 at room temperature. These reactions gave 3-alkylamino-5-arylthiophenes containing various substituents, which comprised, respectively, alkoxycarbonyl, nitro, cyano, p-toluenesulfonyl, 4-nitrophenyl, and diethylphosphono groups at C-2 in good yields. The reaction of 3-methylamino- 3-methylthio-1-phenylthioxopropene with malonic acid or Meldrum's acid under the same conditions gave 3-methylamino-5-phenylthiophene. Similarly, treatment of 3-methylamino-3-methylthio-1-phenylthioxopropene with various enolizable cyclic ketones such as 4-hydroxy-6-methyl-2-pyrone, homophthalic anhydride, 2-hydroxy1,4-benzoquinone, and 1,3-diethyl-2-thiobarbituric acid gave thieno[3,2-b]pyridin-4-one, thieno[3,2c]isoquinolin-5-one, thieno[3,2- c]benzazepine-1,6-dione, and thieno[3,2-d]pyrimidine-2,4-dione, respectively.
